N-CSR

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED
MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number			811-01829
Columbia Acorn Trust
(Exact name of registrant as specified in charter)
One Financial Center, Boston, Massachusetts					02111
(Address of principal executive offices)					(Zip code)
James R. Bordewick, Jr., Esq. Columbia Management Advisors, LLC One Financial Center Boston, MA 02111
(Name and address of agent for service)
Registrant’s telephone number, including area code:				1-617-426-3750
Date of fiscal year end:	December 31, 2007
Date of reporting period:		December 31, 2007

Form N-CSR is to be used by management investment companies to file reports with the Commission not later than 10 days after the transmission to stockholders of any report that is required to be transmitted to stockholders under Rule 30e-1 under the Investment Company Act of 1940 (17 CFR 270.30e-1). The Commission may use the information provided on Form N-CSR in its regulatory, disclosure review, inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-CSR, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-CSR unless the Form displays a currently valid Office of Management and Budget (“OMB”) control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to Secretary, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0609. The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. § 3507.

Item 1. Reports to Stockholders.

4Q

Columbia Acorn
Family of Funds

Class Z Shares

Annual Report

December 31, 2007

n  Columbia^SM   Acorn® Fund

n  Columbia^SM Acorn International®

n  Columbia^SM Acorn USA®

n  Columbia^SM Acorn International Select^SM

n  Columbia^SM Acorn Select^SM

n  Columbia^SM Thermostat Fund^SM

Managed by Columbia Wanger Asset Management, L.P.

NOT FDIC INSURED

NOT BANK ISSUED

May Lose Value

No Bank Guarantee

Columbia Acorn Family of Funds

Descriptions of indexes included in this report:

•Standard & Poor's (S&P) 500 Index tracks the performance of 500 widely held, large-capitalization U.S. stocks.

•Standard & Poor's (S&P) MidCap 400 Index is a market value-weighted index that tracks the performance of 400 mid-cap U.S. companies.

•Russell 2000® Index measures the performance of the 2,000 smallest companies in the Russell 3000 Index, which represents approximately 8% of the total market capitalization of the Russell 3000 Index.

•Russell 2500^TM Index measures the performance of the 2,500 smallest companies in the Russell 3000 Index, which represents approximately 17% of the total market capitalization of the Russell 3000 Index.

•S&P/Citigroup EMI Global ex-US Index is an unmanaged index consisting of the bottom 20% of institutionally investable capital of developed and emerging countries, outside the United States.

•S&P/Citigroup Global ex-US Cap Range $500mm-$5bn Index is a subset of the broad market selected by the index sponsor representing the mid- and small-cap developed and emerging markets, excluding the United States.

•Morgan Stanley Capital International Europe, Australia, Far East (MSCI EAFE) Index is a capitalization-weighted index that tracks the total return of common stocks in 21 developed-market countries within Europe, Australia and the Far East.

•S&P/Citigroup World ex-US Cap Range $2–10B Index is a subset of the broad market selected by the index sponsor representing the mid-cap developed market excluding the United States.

•Lipper Indexes include the largest funds tracked by Lipper, Inc. in the named category. Lipper Mid-Cap Growth Index, 30 mid-cap growth funds; Lipper Mid-Cap Core Funds Index, 30 mid-cap core funds; Lipper International Funds Index, 30 largest non-U .S. funds, not including non-U.S. small-cap funds; Lipper International Small-Cap Funds Index, 10 largest non-U.S. funds investing in small-cap companies, including Columbia Acorn International; Lipper Small-Cap Core Funds Index, 30 largest small-cap core funds, including Columbia Acorn Fund; Lipper Flexible Portfolio Funds Index, an equal dollar-weighted index of the 30 largest mutual funds within the Flexible Portfolio fund classification, as defined by Lipper.

•Lehman Brothers U.S. Credit Intermediate Bond Index is the intermediate component of the U.S. Credit Index. The U.S. Credit Index includes publicly issued U.S. corporate and foreign debentures and secured notes that meet specified maturity, liquidity, and quality requirements.

Unlike mutual funds, indexes are not managed and do not incur fees or expenses. It is not possible to invest directly in an index.

The views expressed in the "Letter to Shareholders," "Squirrel Chatter II" and "In a Nutshell" commentary reflect the current views of the respective authors. These views are not guarantees of future performance and involve certain risks, uncertainties and assumptions that are difficult to predict so actual outcomes and results may differ significantly from the views expressed. These views are subject to change at any time based upon economic, market or other conditions and the respective parties disclaim any responsibility to update such views. These views may not be relied on as investment advice and, because investment decisions for a Columbia Acorn Fund are based on numerous factors, may not be relied on as an indication of trading intent on behalf of any particular Columbia Acorn Fund. References to specific company securities should not be construed as a recommendation or investment advice and there can be no assurance that as of the date of publication of this report, the securities mentioned in each Fund's portfolio are still held or that the securities sold have not been repurchased.

Letter to Shareholders from the
Columbia Acorn Trust Board of Trustees

The Columbia Acorn Trust Board of Trustees has 10 independent Trustees and Ralph Wanger, the retired founder of the predecessor company of Columbia Wanger Asset Management ("CWAM"), the investment adviser of the Columbia Acorn Family of Funds ("Acorn Funds"). Charles P. McQuaid, the Chief Investment Officer of CWAM, is also a Trustee. This diverse and qualified complement of shareholder Trustees with a strong independent majority provides the foundation of a decision process without undue influence of conflicting interests.

Governance of the Acorn Funds is driven through an active committee structure. The issues and challenges we face in today's environment can be complex and frequently require an in-depth review and analysis by committee. Our governance process is more efficient and effective when issues are studied in-depth in preparation of making a recommendation for consideration by the full Board of Trustees.

The function and purpose of each standing committee of the Board of Trustees that meets regularly is specified in the committee's charter. Trustees and chairpersons are nominated and elected to these committees based on their background and experience to meet the purpose and objective of the respective committee with recognition of a preference to achieve some balance of the workload among all Trustees. Committees that meet regularly are Audit, Compliance, Contract, Governance, Investment Performance and Valuation. All chairpersons are independent trustees with the exception of the Valuation committee which is chaired by Charles P. McQuaid. In addition to our standing committees, we have in the past established limited purpose committees, and are prepared to do so in the future to review and analyze specific issues or topics as they arise.

The Trustees initiated and approved changes relating to certain Acorn Funds during the year.

•  Approved a strategy for Acorn Select Fund generally to invest in 30 to 60 companies (up from 20 to 40 companies) with market capitalizations under $20billion. We also increased the limit for the Fund's investment in non U.S. based companies to 33% from 25%.

•  Established a new advisory fee breakpoint for Acorn International Select Fund for total assets of $500 million and over at .90%, a reduction from .94%.

•  We discontinued the sale of Class B shares of all Acorn Funds with the exception of dividend reinvestments, effective February 29, 2008.

•  The minimum investment for new shareholders in the Acorn Select Fund was increased to $100,000 from $50,000.

One critical responsibility of your Board of Trustees is to have a complement of Trustees to achieve multiple objectives including planned succession and continuity in the future. Two new independent Trustees were elected by the Board in 2007: Laura A. Born and Maureen M. Culhane. They are exceptionally qualified for your Board.

At the conclusion of our September, 2007 meeting, Patricia A.Werhane, an independent Trustee, concluded her term of service on the Board. On behalf of all shareholders we thank her for her commitment and outstanding service to the Acorn Funds.

As we begin a new year, your Trustees are confident that the investment management responsibilities for the Acorn Funds are in strong hands. We have renewed the investment advisory agreement for each of the Acorn Funds with CWAM through July 2008 and have again placed our trust in CWAM's aim to meet shareholder expectations. Consistency and continuity have always been a key strength of CWAM and its predecessors in serving the Acorn Funds. CWAM is led by Charles P. McQuaid. He has been serving the Acorn Funds for over 29 consecutive years. He is surrounded by a group of talented portfolio managers, some who joined him in serving the Acorn Funds in the 1990's and others in more recent years.

Accompanying this letter is the 2007 annual report to shareholders of the Acorn Funds that includes performance information from your portfolio managers. We thank our fellow shareholders for their interest and investment in the Acorn Funds.

Robert E. Nason
Independent Chairman of the Board of Trustees
Columbia Acorn Trust

Columbia Acorn Family of Funds

Table of Contents

Performance At A Glance	1
Squirrel Chatter II: Ponzi Schemes and Politicians' Dreams	2
Understanding Your Expenses	4
Columbia Acorn Fund
In a Nutshell	6
At a Glance	7
Major Portfolio Changes	18
Statement of Investments	20
Columbia Acorn International
In a Nutshell	8
At a Glance	9
Major Portfolio Changes	32
Statement of Investments	34
Portfolio Diversification	40
Columbia Acorn USA
In a Nutshell	10
At a Glance	11
Major Portfolio Changes	41
Statement of Investments	42
Columbia Acorn International Select
In a Nutshell	12
At a Glance	13
Major Portfolio Changes	48
Statement of Investments	49
Portfolio Diversification	52

Columbia Acorn Select
In a Nutshell	14
At a Glance	15
Major Portfolio Changes	53
Statement of Investments	54
Columbia Thermostat Fund
In a Nutshell	16
At a Glance	17
Statement of Investments	57
Columbia Acorn Family of Funds
Statements of Assets and Liabilities	58
Statements of Operations	59
Statements of Changes in Net Assets	60
Financial Highlights	64
Notes to Financial Statements	66
Report of Independent Registered Public Accounting Firm	73
Federal Income Tax Information	74
Management Fee Evaluation of the Senior Officer	75
Board Approval of the Advisory Agreement	80
Board of Trustees and Management of Columbia Acorn Funds	83
Columbia Acorn Family of Funds Information	86

2007 Year-End Distributions

The following table details the Funds' year-end distributions. The record date for all Funds except Columbia Thermostat Fund was December 10, 2007. The ex-dividend date was December 11, 2007, and the payable date was December 12, 2007. For Columbia Thermostat Fund, the record date was December 20, 2007. The ex-dividend date was December 21, 2007, and the payable date was December 24, 2007.

	Short-term Capital Gains		Long-term Capital Gains		Ordinary Income		Reinvestment Price
Columbia Acorn Fund	$	0.1126	$	1.8022	$	0.1152	$	29.78
Columbia Acorn International	$	0.1785	$	2.9312	$	0.2191	$	44.01
Columbia Acorn USA		None	$	1.4262		None	$	28.02
Columbia Acorn International Select		None	$	1.7656	$	0.1377	$	32.07
Columbia Acorn Select		None	$	0.4558		None	$	28.62
Columbia Thermostat Fund	$	0.3907	$	0.1072	$	0.5063	$	12.23

Columbia Acorn Family of Funds

Performance At A Glance Class Z Average Annual Total Returns through 12/31/07

	NAV on 12/31/07		4th quarter*			1 year			3 years			5 years			10 years			Life of Fund
Columbia Acorn Fund (ACRNX)(6/10/70)	$	29.61		-3.22	%		7.69	%		11.71	%		19.80	%		13.45	%		16.06	%
Russell 2500				-4.32	%		1.38	%		8.38	%		16.99	%		9.01	%		NA
S&P 500				-3.33	%		5.49	%		8.62	%		12.83	%		5.91	%		11.80	%
Lipper Small-Cap Core Funds Index				-4.23	%		1.92	%		7.62	%		15.76	%		8.34	%		NA
Lipper Mid-Cap Core Funds Index				-3.44	%		6.34	%		9.71	%		15.80	%		9.16	%		NA
Columbia Acorn International (ACINX) (9/23/92)	$	43.60		-2.01	%		17.28	%		24.33	%		29.75	%		14.95	%		14.71	%
S&P/Citigroup EMI Global ex-US				-3.36	%		12.37	%		21.50	%		29.16	%		13.02	%		10.66	%
S&P/Citigroup Global ex-US Cap Range $500mm-$5bn				-2.73	%		15.98	%		22.20	%		29.82	%		13.63	%		11.35	%
MSCI EAFE Index				-1.75	%		11.17	%		16.83	%		21.59	%		8.66	%		9.06	%
Lipper Int'l Small-Cap Funds Index				-4.89	%		9.90	%		20.32	%		28.46	%		14.99	%		NA
Columbia Acorn USA (AUSAX) (9/4/96)	$	27.97		-3.25	%		3.46	%		8.17	%		17.57	%		9.97	%		12.98	%
Russell 2000				-4.58	%		-1.57	%		6.80	%		16.25	%		7.08	%		9.01	%
Lipper Small-Cap Core Funds Index				-4.23	%		1.92	%		7.62	%		15.76	%		8.34	%		10.01	%
S&P 500				-3.33	%		5.49	%		8.62	%		12.83	%		5.91	%		9.14	%
Columbia Acorn Int'l Select (ACFFX) (11/23/98)		$32.02		0.80%			21.86%			24.41%			27.65%			NA			14.90%
S&P/Citigroup World ex-US Cap Range $2-10B				-4.33	%		9.84	%		19.13	%		25.94	%		NA			12.48	%
MSCI EAFE Index				-1.75	%		11.17	%		16.83	%		21.59	%		NA			7.86	%
Lipper International Funds Index				-1.00	%		14.25	%		18.49	%		21.82	%		NA			9.26	%
Columbia Acorn Select (ACTWX) (11/23/98)	$	28.41		-5.24	%		9.20	%		13.23	%		17.59	%		NA			14.61	%
S&P MidCap 400				-2.73	%		7.98	%		10.27	%		16.20	%		NA			11.50	%
Lipper Mid-Cap Growth Index				-0.03	%		21.41	%		13.88	%		17.93	%		NA			8.70	%
S&P 500				-3.33	%		5.49	%		8.62	%		12.83	%		NA			4.25	%
Columbia Thermostat Fund (COTZX) (9/25/02)†		$12.26		0.35%			8.49%			8.26%			10.66%			NA			10.93%
S&P 500				-3.33	%		5.49	%		8.62	%		12.83	%		NA			13.78	%
Lehman Brothers U.S. Credit Intermediate Bond Index				2.17	%		5.60	%		3.83	%		4.49	%		NA			4.85	%
Lipper Flexible Portfolio Funds Index				-0.21	%		9.57	%		9.53	%		12.10	%		NA			12.65	%

*Not annualized.

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in a Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Please visit columbiafunds.com for daily and most recent month-end updates. Net asset value (NAV) returns do not include sales charges or contingent deferred sales charges (CDSC). Class Z shares are sold only at NAV with no Rule 12b-1 fee. Class Z shares have limited eligibility and the investment minimum requirement may vary. Only eligible investors may purchase Class Z shares of the Funds, directly or by exchange. Please see each Fund's prospectus for eligibility and other details.

Performance results reflect any voluntary waivers or reimbursement of Fund expenses by the investment adviser and/or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results would have been lower.

Annual operating expense ratios are as stated in each Fund prospectus that is current as of the date of this report and differences in expense ratios disclosed elsewhere in this report may result from including fee waivers and reimbursements as well as different time periods used in calculating the ratios. Columbia Acorn Fund Class Z: 0.75%. Columbia Acorn International Class Z: 0.94%. Columbia Acorn USA Class Z: 1.01%. Columbia Acorn International Select Class Z: 1.28%. Columbia Acorn Select Class Z: 0.98%. Columbia Thermostat Fund has a contractual expense waiver or reimbursement that expires April 30, 2008. Expense ratios without and with the contractual waiver, including fees and expenses associated with the Fund's investments in other investment companies, for Class Z shares are 1.10% and 0.94%, respectively. Absent the waiver or reimbursement, performance results would have been lower.

†A "fund of funds" bears its allocable share of the costs and expenses of the underlying funds in which it invests. Such funds are thus subject to two levels of fees and potentially higher expense ratios than would be associated with an investment in an investment fund that invests and trades directly in financial instruments under the direction of a single manager.

All results shown assume reinvestment of distributions and do not reflect the deduction of taxes that a shareholder would pay on fund distributions or the redemption of fund shares.

All indexes are unmanaged. It is not possible to invest directly in an index. For index definitions, see the inside front cover of this report.

1

Squirrel Chatter II: Ponzi Schemes and Politicians' Dreams

Each December I attend The University of Chicago Business Forecast luncheon. Typically the event features economic forecasts by two economists, plus a summary of world political and economic issues provided by Professor Marvin Zonis.¹ At this year's luncheon Professor Zonis stated that the U.S. Government had $50 trillion of unfunded liabilities. That's a staggering figure! Could it really be correct?

"Trust Me" Trust Funds

I've found that there is no precise U.S. Government unfunded liability number, though there are estimates. The U.S. Government Accountability Office (GAO) notes material weaknesses in federal government accounting in general, but has expressed an unqualified opinion on its 2007 Statement of Social Insurance. Any calculation of unfunded liabilities requires numerous actuarial assumptions plus a time horizon. The calculations by various government agencies cover liabilities for 75 years into the future.

However, it does appear that Professor Zonis' $50 trillion estimate was wrong. That number is now too low. On December 17, 2007, the GAO estimated that the U.S. Government's total reported liabilities, net social insurance commitments, and other fiscal exposures were approximately $53 trillion.² With apologies to the late Senator Everett Dirksen (Republican: Illinois), it seems that a trillion here and a trillion there adds up.³

Despite well-publicized concerns about Social Security, Medicare is in worse shape. Created in the 1930s, Social Security seems to have been a warm-up for bigger unfunded liabilities later on. Social Security is better funded, as Social Security tax rates are higher than Medicare tax rates. Medicare was signed into law in 1965 and spending for the program quickly ran out of control. The original cost estimate for Medicare hospital insurance in 1990, for example, was $9 billion; the actual cost that year hit $67 billion!⁴ According to the GAO, Medicare alone has over $36 trillion of unfunded liabilities.

But what of the Social Security and Medicare Trust Funds, the Funds that politicians promised to put in a "lock box?" It turns out the politicians spent the money elsewhere and the Trust Funds loaned their money to the U.S. Treasury by buying government bonds. The Trust Funds have no true third-party assets, but simply have promises from the U.S. Treasury to pay in the future. In order for the payments to be made the Treasury will have to raise taxes, cut other spending, borrow or print money.

What was the latest change that politicians made concerning unfunded liabilities? They increased them by adding prescription drugs to Medicare's benefits. This addition is noteworthy for three reasons. First, little new funding was created; enrollee premiums cover only about 25% of costs. Second, the program's costs and benefits are highly skewed. Baby boomers will have a net benefit of about $20,000 each while younger workers and future generations will have net costs of between $2,500 and $4,200 each.⁵ Third, when the new benefits were fully implemented in 2006, they drove a 19% increase in Medicare costs, the largest increase in decades. Over $10 trillion of Medicare's unfunded liability is from the drug program.

What are this year's presidential candidates saying about the unfunded liability problem? Virtually nothing and, even though taxpayers cannot afford Social Security, Medicare and other existing programs, some candidates are touting new proposals that substantially broaden federal health care spending. These plans include additional entitlements and mandatory, subsidized, health insurance participation. Cost estimates are dubious but range from $50 to $120 billion yearly.

Given the huge existing liabilities and proposals for additional benefits, it appears that the U.S. Government is operating an enormous Ponzi Scheme.⁶ Initial participants benefit but most taxpayers are likely to lose.

Large Liabilities and Possible Solutions

$53 trillion is a huge number, nearly four times all the goods and services produced in the United States in 2007. Currently Social Security is running a yearly surplus while Medicare is running a deficit. But the aging of baby boomers is driving yearly Medicare and Social Security spending higher, so the programs' cash needs will become very large in the next decade. Medicare deficits are projected to consume 25% of all federal income taxes by 2020. By 2050, Social Security, Medicare, and Medicaid will grow from 9% to 18% of GDP. This contrasts to total federal spending averaging about 20% of GDP over the last 50 years.⁷

Some of the richest people in America say their taxes are too low. What if they were taxed at 100%? Not 100% of income but 100% of their net worth! This "Che Guevara lite" (confiscation without murder) solution, if

2

applied to the 2007 Forbes list of the richest 400 Americans, would yield a one-time receipt of $1.54 trillion. That would cover 2.9% of the problem, but is of course not a real solution as it would destroy capitalism.

How about raising tax rates on all of us? The Laffer Curve⁸ exists—there is an income tax rate that will yield the highest dollar amount of taxes, and that rate appears to be well under 100%. Even famed British economist John Maynard Keynes said that reducing too-high tax rates results in higher tax revenues. Very high tax rates choke economic activity and spur taxpayers to take legal and illegal measures to reduce payments.

Since federal income taxes began in 1913, there have been three rounds of major income tax rate cuts in the United States, and each resulted in faster economic growth and, ultimately, higher taxes collected. Paradoxically, though the rate cuts provided those with higher incomes the largest benefits, higher income people ended up paying greater percentages of total tax collections. A number of countries, including former Soviet republics, have adopted low, flat income tax rates and have seen economic growth surge and tax receipts increase.

No one knows what income tax rates create the highest tax revenues over the long run. In the last 50 years, the highest marginal tax rates in the United States have varied from a pre-Kennedy rate cut peak of 91% to a post-Reagan rate cut trough of 28%. Surprisingly, total federal government revenues as a percentage of GDP during that period have varied modestly, from 16.1% to 20.9%. Fiscal 2007 revenues were a bit above the midpoint, at 18.8% of GDP.⁹

While somewhat higher tax rates would probably increase near-term tax revenues, it is unlikely that substantially higher income tax rates alone can boost government receipts to the 30% or so of GDP eventually needed to fully fund the promised benefits. Massive value added taxes or sales taxes would likely be needed to provide tax revenue percentages that high. But huge tax hikes of any sort are likely to hurt economic growth, and additional solutions are needed.

As substantial liabilities become due in the next decade, there is an increased likelihood that voters will elect more courageous politicians that will strive to control spending and enact needed reforms. Perhaps the best single reform would be to restore more free market elements to our health care system. There needs to be more price transparency plus incentives for individuals and health care providers to control spending. Streamlined drug approval processes and additional tort reform would also help.

Incentives for innovation, rather than arbitrary price controls, are crucial. Improved technology has enabled over a 99.99% reduction in the cost of genome mapping in the last seven years. As costs continue to drop and advances continue to be made in biotechnology and pharmaceuticals, new ways to diagnose, treat and cure diseases are likely. Treatments customized to genetic factors promise to be much more effective and result in fewer side effects than many current drugs. The Columbia Acorn Funds have begun to own stocks in companies that are pursuing genetic tests, novel drugs and devices, plus information technology for better managing health care administration.

Outside the health care sector, Professor Jeremy Siegel has suggested that a solution for America's savings and retirement crisis will be sales of American assets to foreigners, especially those from countries with higher savings rates and younger populations. Innovative small- and mid-cap companies appear particularly attractive to foreigners, especially now that the dollar has weakened. The sale has begun, as mentioned in Columbia Acorn Fund's nutshell discussion on Page 6.

Charles P. McQuaid

President and Chief Investment Officer
Columbia Wanger Asset Management, L.P.

Opinions expressed in "Squirrel Chatter II" are those of the author and are not necessarily those of Columbia Wanger Asset Management, its parent organizations, or the Columbia Acorn Trust Board.

¹  Marvin Zonis is a professor emeritus at the Graduate School of Business at The University of Chicago, where he teaches courses on International Political Economy, Leadership and Business Strategy in the Era of E-Commerce.

²  Estimates by the Congressional Budget Office, Medicare trustees, and some private sources are higher.

³  Dirksen has been quoted as saying, "A billion here and a billion there, and pretty soon you're talking real money," but the Dirksen Congressional Center has been unable to verify the statement.

⁴  Source: American Enterprise Institute for Public Policy Research website, www.aei.org, "Medicare Prescription Drugs: Medical Necessity Meets Fiscal Insanity," by Joseph Antos and Jagadeesh Gokhale. Posted February 17, 2005.

⁵  Ibid.

⁶  In the 1920's, Charles Ponzi enticed investors with a bogus investment opportunity that promised a 40% return on their investment in just 90 days. Early investors were paid with dollars from later investors but most lost their money. Ponzi served four years in prison for this fraud, and then proceeded to promote other dubious ventures. He died in a charity ward of a Rio de Janeiro hospital in 1949.

⁷  Included in testimony on the future of Social Security presented by the Concord Coalition (www.concordcoalition.org) to a Senate special committee on aging, February 3, 2005.

⁸  The Laffer Curve is used to illustrate the concept of taxable income elasticity, the idea that government can maximize tax revenue by setting tax rates at an optimum point and that neither a 0% tax rate nor a 100% tax rate will generate government revenue. The curve was popularized by U.S. economics professor Arthur Laffer (b. 1940).

⁹  Source: Congressional Budget Office.

3

Understanding Your Expenses

As a Fund shareholder, you incur two types of costs. There are transaction costs, which generally include sales charges on purchases and may include redemption or exchange fees. There are also ongoing costs, which generally include investment advisory fees, Rule 12b-1 fees (distribution and service fees) and other Fund expenses. The following information is intended to help you understand your ongoing costs of investing in the Columbia Acorn Funds and to compare these costs with the ongoing costs of investing in other mutual funds.

Analyzing Your Fund's Expenses

To illustrate these ongoing costs, we have provided examples and calculated the expenses paid by investors in the Class Z shares of the Columbia Acorn Funds for the last six months. The information in the following table is based on an initial investment of $1,000.00, which is invested at the beginning of the reporting period and held for the entire period. Expense information is calculated two ways and each method provides you with different information. The amount listed in the "Actual" column is calculated using each Fund's actual operating expenses and total return for the period. The amount listed in the "Hypothetical" column assumes that the return each year is 5% before expenses and then applies each Fund's actual expense ratio for the period to the hypothetical return. You should not use the hypothetical account values and expenses to estimate either your actual account balance at the end of the period or the expenses yo u paid during the reporting period. See the "Compare With Other Funds" information for details on using the hypothetical data.

July 1, 2007 – December 31, 2007

	Account value at the beginning of the period ($)				Account value at the end of the period ($)				Expenses paid during the period ($)				Fund's annualized expense ratio (%)*
Class Z Shares	Actual		Hypothetical		Actual		Hypothetical		Actual		Hypothetical		Actual
Columbia Acorn Fund		1,000.00		1,000.00		965.52		1,021.48		3.67		3.77		0.74
Columbia Acorn International		1,000.00		1,000.00		1,023.49		1,020.57		4.69		4.69		0.92
Columbia Acorn USA		1,000.00		1,000.00		944.80		1,020.27		4.80		4.99		0.98
Columbia Acorn International Select		1,000.00		1,000.00		1,089.98		1,019.26		6.22		6.01		1.18
Columbia Acorn Select		1,000.00		1,000.00		935.32		1,020.67		4.39		4.58		0.90
Columbia Thermostat Fund		1,000.00		1,000.00		1,038.92		1,023.95		1.28		1.28		0.25

Expenses paid during the period are equal to each Fund's annualized expense ratio, multiplied by the average account value over the period and then multiplied by the number of days in the Fund's most recent fiscal half-year and divided by 365.

Had the investment adviser and/or any of its affiliates not waived fees or reimbursed a portion of expenses, account value at the end of the period would have been reduced.

It is important to note that the expense amounts shown in the table are meant to highlight only ongoing costs of investing in the Funds and do not reflect any transaction costs, such as sales charges, redemption or exchange fees. Therefore, the hypothetical examples provided may not help you determine the relative total costs of owning different funds. If these transaction costs were included, your costs would have been higher.

Columbia Thermostat Fund's expenses do not include fees and expenses incurred by the Fund from the underlying portfolio funds in which it invests.

*For the six months ended December 31, 2007.

Compare With Other Funds

Since all mutual funds are required to include the same hypothetical calculations about expenses in shareholder reports, you can use this information to compare the ongoing cost of investing in the Funds with other funds. To do so, compare the 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of other funds. As you compare hypothetical examples of other funds, it is important to note that hypothetical examples are meant to highlight the continuing costs of investing in a fund and do not reflect any transaction costs, such as sales charges, or redemption or exchange fees.

4

Estimating Your Actual Expenses

To estimate the expenses that you actually paid over the period, first you will need your account balance at the end of the period:

•  For shareholders who receive their account statements from Columbia Management Services, Inc., your account balance is available online at columbiafunds.com or by calling Shareholder Services at (800) 922-6769.

•  For shareholders who receive their account statements from their brokerage firm, contact your brokerage firm to obtain your account balance.

1.  Divide your ending account balance by $1,000.00. For example, if an account balance was $8,600.00 at the end of the period, the result would be 8.6.

2.  In the section of the table titled "Expenses paid during the period," locate the amount for your Fund. You will find this number is in the column labeled "Actual." Multiply this number by the result from step 1. Your answer is an estimate of the expenses you paid on your account during the period.

5

Columbia Acorn Fund

In a Nutshell

Charles P. McQuaid

Lead Portfolio Manager

Robert A. Mohn

Co-Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Please visit columbiafunds.com for daily and most recent month-end performance updates.

Fund's Positions

in Mentioned Holdings

as of 12/31/07

FMC Technologies	1.6	%
Fugro	1.5	%
Coach	1.1	%
Ultra Petroleum	1.0	%
Atwood Oceanics	0.6	%
Southwestern Energy	0.5	%
Housing Development Finance	0.5	%
Hong Kong Exchanges and Clearing	0.5	%
AmeriCredit	0.5	%
NAVTEQ	0.5	%
Genlyte Group	0.5	%
Chico's FAS	0.3	%
MGI Pharma	0.2	%

Portfolio holdings are subject to change periodically and may not be representative of current characteristics and holdings.

Columbia Acorn Fund returned 7.69% in 2007, substantially beating the 1.38% return of its primary benchmark, the Russell 2500 Index. The Fund also outperformed the large-cap S&P 500's gain of 5.49%, which was gratifying as small caps tended to underperform large caps during the period.

The equity markets were poor in the fourth quarter; both volatile and down. Columbia Acorn Fund dropped 3.22% in the quarter, falling less than the small-cap benchmarks and essentially in line with the mid- and large-cap benchmarks.

Energy stocks helped performance substantially during the year and somewhat during the quarter. Wellhead maker FMC Technologies was the Fund's largest dollar winner in 2007. It provided a blowout 84% gain as earnings grew rapidly. Dutch oilfield service provider Fugro sounded out a 63% profit. A third company benefiting from the pursuit of offshore oil, Atwood Oceanics, surged more than 104% in the year and 31% in the fourth quarter. Several oil and gas producers were also hot. Southwestern Energy jumped 59% in the year and 33% in the quarter, while Ultra Petroleum appreciated 50% and 15%, respectively. We thank our energy analyst Bill Doyle for these picks.

Columbia Acorn Fund had a record 39 takeovers of portfolio companies announced in 2007, including six in the fourth quarter. Kronos, a labor management software developer, booked the largest dollar gain among takeovers during the year, rising 50%. Two takeovers that were announced during the fourth quarter were also big winners for the year. Map data provider NAVTEQ climbed 114% in 2007; it agreed to be bought by Finland's Nokia. Specialty pharmaceutical producer MGI Pharma announced a sellout to Japan's Eisai, and provided a healthy gain of more than 116%. Also in the fourth quarter, lighting fixtures maker Genlyte Group agreed to sell to Holland's Philips Electronics. It brightened our results as the Fund's largest dollar winner in the quarter, showing a 47% profit. While sellouts to private equity slowed in late 2007, sellouts to foreign companies continued.

Foreign stocks were up 26.17%* during the year, but were off 3.03% during the quarter. Hong Kong Exchanges and Clearing rose over 160% in 2007, and provided the Fund's second largest dollar gains. Fugro, mentioned above, was the Fund's third largest dollar winner. India's Housing Development Finance benefited from that country's economic growth and jumped 98%. We trimmed Columbia Acorn Fund's foreign holdings to 11.6% of assets at year-end.

Consumer stocks hurt. Chico's FAS fell 57% in the year and 36% in the quarter, largely on fashion missteps. Coach executed splendidly, but ended the year off 29% as it fell 35% in the quarter due to macroeconomic concerns. Finance company AmeriCredit lost 49% in the year and 27% in the quarter as investors worried about used car loans and sources of funding.

We are pleased that our stock picking rebounded strongly in 2007 after a mildly disappointing 2006. The early 2008 market turmoil feels disconcerting, but may provide favorable purchasing opportunities.

*This return is not comparable to mutual fund returns, as it is gross of fees and other expenses and does not portray the cash effects incurred by actual mutual funds. Columbia Acorn Fund's foreign stockholdings were heavily weighted toward energy during the periods covered and were not purchased as a balanced, stand-alone portfolio.

Small- and mid-cap stocks are often more volatile and less liquid than the stocks of larger companies. Small companies may have a shorter history of operations than larger companies and may have a less diversified product line, making them more susceptible to market pressure. International investments involve greater potential risks, including less regulation, currency fluctuations, economic instability and political developments.

6

Columbia Acorn Fund (ACRNX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Class Z)

through December 31, 2007

Inception 6/10/70	1 year			5 years			10 years
Returns before taxes		7.69	%		19.80	%		13.45	%
Returns after taxes on distributions		6.48			18.89			12.01
Returns after taxes on distributions and sale of fund shares		6.65			17.48			11.41
Russell 2500 (pretax)		1.38			16.99			9.01
S&P 500 (pretax)		5.49			12.83			5.91

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the additional tax impact of long-term gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class Z shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes.

The Fund's Class Z shares annual operating expense ratio, as stated in the current prospectus, is 0.75%.

Columbia Acorn Fund Portfolio Diversification

as a % of net assets as of 12/31/07

Columbia Acorn Fund Top 10 Holdings

as a % of net assets as of 12/31/07

1.	FMC Technologies Oil & Gas Wellhead Manufacturer	1.6%
2.	Fugro (Netherlands) Oilfield Services	1.5%
3.	Abercrombie & Fitch Teen Apparel Retailer	1.3%
4.	Expeditors International of Washington International Freight Forwarder	1.2%
5.	Ametek Aerospace/Industrial Instruments	1.2%
6.	Coach Designer & Retailer of Branded Leather Accessories	1.1%
7.	Eaton Vance Specialty Mutual Funds	1.1%
8.	People's United Connecticut Savings & Loan	1.0%
9.	SEI Investments Mutual Fund Administration & Investment Management	1.0%
10.	Donaldson Industrial Air Filtration	1.0%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $75,000 Investment in Columbia Acorn Fund (Class Z)

June 10, 1970 through December 31, 2007

This graph compares the results of $75,000 invested in Columbia Acorn Fund at inception on June 10, 1970 to the S&P 500 and to an initial $238,325 investment in the Russell 2500 on the index's December 31, 1978 inception date. The indexes are unmanaged and returns for both the indexes and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $19.9 billion

*A $75,000 investment in Columbia Acorn Fund at inception appreciated to $238,325 on December 31, 1978, the inception date of the Russell 2500. For comparison with the Russell 2500, we assigned the index the same value as the Fund at index inception.

7

Columbia Acorn International

In a Nutshell

P. Zachary Egan

Co-Portfolio Manager

Louis J. Mendes III

Co-Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Please visit columbiafunds.com for daily and most recent month-end performance updates.

Fund's Positions

in Mentioned Holdings

as of 12/31/07

Atwood Oceanics	1.3	%
Hong Kong Exchanges and Clearing	1.2	%
Smit Internationale	1.2	%
Singapore Exchange	1.1	%
Taewoong	0.5	%
Sung Kwang Bend	0.5	%

Portfolio holdings are subject to change periodically and may not be representative of current characteristics and holdings.

Columbia Acorn International gained 17.28% in 2007, 4.91% ahead of the S&P/Citigroup EMI Global ex-US Index ("EMI") and 6.11% ahead of the large-cap MSCI EAFE Index ("EAFE"). During the fourth quarter, the Fund fell 2.01%, while the EMI declined by 3.36%. The Fund's results for the year were driven most notably by strong underlying performance in continental Europe and in the emerging markets, which more than offset declining markets in Japan and the United Kingdom. On a sector basis, energy and financial stocks all posted strong absolute and relative performance in the Fund. Finally, the weak performance of the U.S. dollar translated into a net gain of 6.7% for our shareholders.

For the eighth consecutive year, international small-cap stocks, as measured by the EMI Index, have outperformed international large-cap stocks, as measured by the EAFE Index. Strong underlying growth in China, India and several other large emerging economies drove global demand for energy, raw materials and industrial goods for yet another year. Many of the Fund's industrial exporters reported record profitability as pricing power and capacity utilization remained high. For example, Sung Kwang Bend and Taewoong, two Korean industrial companies involved in global energy infrastructure projects, rose 273% and 172%, respectively. Export activity kept Asian and European ports busy. Smit Internationale, a Dutch operator of tugboats and salvage vessels, rose 98% on strong demand for its services as seaborne trade continues to grow at a considerably higher rate than global GDP.

During the year, the only significant change in average regional exposure within the portfolio was an increase in Asia ex-Japan investments from 8% to 13% of the Fund's equity, funded primarily by a reduction in the United Kingdom and Ireland from 16% to 11%. This reallocation of assets had a favorable impact on the Fund. Our UK/Ireland positions averaged a mid-single digit negative return while those in Asia ex-Japan returned over 60%, representing both the best and worst performing regional returns. This can be explained in large part by the subprime crisis in the United Kingdom, which had broad repercussions across the market. While in Asia ex-Japan, robust economic development drove high volumes on the companies that operate the regional equity and derivative exchanges, in which the Fund held sizable positions. Hong Kong Exchanges and Clearing and Singapore Exchange appreciated more than 160% and 152%, respectively, in the y ear.

At the sector level, the Fund's ongoing overweight in energy services companies was helpful. Energy prices remained near record levels, underpinning solid earnings growth in oil services companies, as they expand to meet growing demand from the large oil conglomerates. The Fund's energy stocks, representing 7.6% of equity, generated over a 50% return to shareholders. Outstanding stocks included Atwood Oceanics, a provider of offshore drilling rigs, which increased more than 104% in 2007.

As we look ahead to 2008, the impact of the continuing crisis in subprime mortgages in the United States and United Kingdom on global markets remains a looming concern. While many portfolio companies continue to report excellent business fundamentals, as we write this in mid-January the markets appear to be taking into consideration the distinct possibility of a U.S. and European recession. We expect volatility to remain high. As long-term, fundamental investors, we will work to take advantage of the pricing anomalies this will likely create.

Thank you for your continued investment in Columbia Acorn International.

International investments involve greater potential risks, including less or different regulation, currency fluctuations, economic instability and political developments. Investments in small- and mid-cap companies may be subject to greater volatility and price fluctuations because they may be thinly traded and less liquid. Investing in emerging markets may involve greater risks than investing in more developed countries.

8

Columbia Acorn International (ACINX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Class Z)

through December 31, 2007

Inception 9/23/92	1 year			5 years			10 years
Returns before taxes		17.28	%		29.75	%		14.95	%
Returns after taxes on distributions		16.01			28.91			13.89
Returns after taxes on distributions and sale of fund shares		13.19			26.75			13.08
S&P/Citigroup EMI Global ex-US (pretax)		12.37			29.16			13.02
S&P/Citigroup Global ex-US Cap Range $500mm-$5bn (pretax)		15.98			29.82			13.63

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the additional tax impact of long-term gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class Z shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes.

The Fund's Class Z shares annual operating expense ratio, as stated in the current prospectus, is 0.94%.

Columbia Acorn International Portfolio Diversification

as a % of net assets as of 12/31/07

Columbia Acorn International Top 10 Holdings

as a % of net assets as of 12/31/07

1.	Fugro (Netherlands) Oilfield Services	1.9%
2.	Hexagon (Sweden) Measurement Equipment & Polymers	1.4%
3.	SES Global (France) Satellite Broadcasting Services	1.4%
4.	Intralot (Greece) Lottery & Gaming Systems & Services	1.3%
5.	Atwood Oceanics (United States) Offshore Drilling Contractor	1.3%
6.	Housing Development Finance (India) Indian Mortgage Lender	1.2%
7.	Hong Kong Exchanges and Clearing (Hong Kong) Hong Kong Equity & Derivatives Market Operator	1.2%
8.	Smit Internationale (Netherlands) Harbor & Offshore Towage & Marine Services	1.2%
9.	Suzano (Brazil) Brazilian Pulp & Paper Producer	1.2%
10.	ShawCor (Canada) Oil & Gas Pipeline Products	1.1%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn International (Class Z)

September 23, 1992 through December 31, 2007

This graph compares the results of $10,000 invested in Columbia Acorn International at inception on September 23, 1992 to the S&P/Citigroup EMI Global ex-US and the S&P/Citigroup Global ex-US Cap range $500mm-$5bn indexes. The indexes are unmanaged and returns for both the indexes and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $5.7 billion

9

Columbia Acorn USA

In a Nutshell

Robert A. Mohn

Lead Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Please visit columbiafunds.com for daily and most recent month-end performance updates.

Fund's Positions

in Mentioned Holdings

as of 12/31/07

FMC Technologies	2.9	%
Atwood Oceanics	2.1	%
Quicksilver Resources	2.0	%
ITT Educational Services	2.0	%
Flir Systems	1.7	%
BioMarin	1.6	%
True Religon Apparel	1.3	%
Tellabs	1.1	%
Oxford Industries	1.0	%
Urban Outfitters	0.9	%
AmeriCredit	0.9	%
World Acceptance	0.8	%
Coach	0.4	%

Portfolio holdings are subject to change periodically and may not be representative of current characteristics and holdings.

Columbia Acorn USA fell 3.25% in the fourth quarter while its benchmark, the Russell 2000 Index, declined 4.58%. For the year ended December 31, 2007, the Fund posted a 3.46% gain, outperforming the Russell 2000, which fell 1.57% for the year, dragged down by the ailing housing and credit markets.

Energy stocks were our biggest winners for both the quarter and the year. Oil service company Atwood Oceanics, an owner of offshore drilling rigs, was up 31% in the quarter and more than 104% for the year. Atwood reported a 100% utilization rate for its rigs in the third quarter and has been able to demand very high day rates all year long. Natural gas and coal seam gas producer Quicksilver Resources gained 27% in the quarter and was up 63% for the year on strong production growth. While not a standout in the quarter, FMC Technologies was another annual winner with an 84% gain on gushing sales of its subsea wellhead and oil production systems.

Two mergers in the fourth quarter, and one from the first, brought in strong gains. Genlyte Group, a manufacturer of commercial lighting fixtures, gained 47% in the quarter (21% for the year). Pharmaceutical company MGI Pharma gained 44% on take-out news in the quarter and ended the year up more than 116%. In the first quarter, labor management software developer Kronos announced it was being sold. It was the Fund's largest position at that time. The stock was eliminated from the portfolio with a 50% annualized gain.

Other winners included Flir Systems, a manufacturer of infrared cameras. The company won several new defense department contracts during the year and posted a 13% gain in the quarter and 97% return for the year. BioMarin gained 42% in the quarter and ended the year up 99% after announcing that the FDA had approved its drug for treating a genetic disorder that affects approximately 20,000 people in the United States. By targeting rare disorders, BioMarin is able to charge higher prices and enjoy longer patent protection periods for its drugs.

While several of the Fund's retail holdings outperformed during the quarter's retail slump—True Religion Apparel gained 21% in the quarter and Urban Outfitters increased 25%—others did not. Oxford Industries fell along with the sales of its Tommy Bahama line, dropping 28% in the quarter and 47% for the year. Accessories retailer Coach also succumbed to the slump, falling 35% in the fourth quarter and 29% for the year.

ITT Educational Services ended the year up 28% but fell 30% in the fourth quarter as student loan financing began to freeze up. Telecom equipment provider Tellabs fell 31% in the quarter and was off 36% for the year on declining revenues. The company has been hurt by the consolidation of major telecommunication providers that, combined, need less equipment. Rounding out the laggards list were AmeriCredit, down 27% in the quarter and 49% for the year, and World Acceptance, off 18% in the quarter and 42% for the year. Both stocks were hurt by the credit market crunch.

After a rocky end to 2007, investors were hoping for better in 2008. But as of the writing of this report, the New Year is off to a poor start as fears of a U.S. recession grow. When tales of economic woe dominate the headlines, long-term investment opportunities tend to sprout. We continue our relentless search for small-cap, niche companies with the ability to exhibit strong business growth over the next three to five years (even while the sky appears to be falling).

Risks include stock market fluctuations due to economic and business developments. Investments in small- and mid-cap companies may be subject to greater volatility and price fluctuations because they may be thinly traded and less liquid.

10

Columbia Acorn USA (AUSAX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Class Z)

through December 31, 2007

Inception 9/4/96	1 year			5 years			10 years
Returns before taxes		3.46	%		17.57	%		9.97	%
Returns after taxes on distributions		2.58			17.09			9.26
Returns after taxes on distributions and sale of fund shares		3.46			15.52			8.57
Russell 2000 (pretax)		-1.57			16.25			7.08

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the additional tax impact of long-term gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class Z shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes.

The Fund's Class Z shares annual operating expense ratio, as stated in the current prospectus, is 1.01%.

Columbia Acorn USA Portfolio Diversification

as a % of net assets as of 12/31/07

Columbia Acorn USA Top 10 Holdings

as a % of net assets as of 12/31/07

1.	FMC Technologies Oil & Gas Wellhead Manufacturer	2.9%
2.	Crown Castle International Communications Towers	2.7%
3.	Atwood Oceanics Offshore Drilling Contractor	2.1%
4.	Ametek Aerospace/Industrial Instruments	2.1%
5.	Abercrombie & Fitch Teen Apparel Retailer	2.0%
6.	Quicksilver Resources Natural Gas & Coal Seam Gas Producer	2.0%
7.	ITT Educational Services Post-secondary Degree Services	2.0%
8.	Time Warner Telecom Fiber Optic Telephone/Data Services	1.9%
9.	Flir Systems Infrared Cameras	1.7%
10.	ESCO Technologies Automatic Electric Meter Readers	1.7%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $75,000 Investment in Columbia Acorn USA (Class Z)

September 4, 1996 through December 31, 2007

This graph compares the results of $75,000 invested in Columbia Acorn USA at inception on September 4, 1996 to the Russell 2000. The index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $1.5 billion

11

Columbia Acorn International Select

In a Nutshell

Christopher J. Olson

Lead Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Please visit columbiafunds.com for daily and most recent month-end performance updates.

Fund's Positions

in Mentioned Holdings

as of 12/31/07

Nintendo	3.6	%
Potash Corp. of Saskatchewan	3.1	%
Diamond Offshore	3.1	%
Hong Kong Exchanges and Clearing	2.2	%
Ibiden	1.9	%
China Shipping Development	1.7	%
Atwood Oceanics	1.6	%
Uranium One	1.3	%
Singapore Exchange	1.2	%
Kenedix	1.0	%

Portfolio holdings are subject to change periodically and may not be representative of current characteristics and holdings.

Columbia Acorn International Select ended the fourth quarter and the year well ahead of its benchmark, the S&P/Citigroup World ex-US Cap Range $2-10B Index. In a rough fourth quarter for nearly all world markets, the Fund gained 0.80% while the benchmark fell 4.33%. For the one-year period, the Fund increased 21.86%, more than doubling the 9.84% gain of the benchmark. As mentioned last quarter, our decision to sell out of banking stocks helped drive outperformance as the credit market turmoil that arose in the second half of the year rocked the financial sector.

Big winners in the quarter and the year included Japan's Nintendo. The stock was up 18% in the quarter and 148% for the year on strong demand for its Wii gaming console and associated video games. Potash Corp. of Saskatchewan was another big winner gaining 35% in the quarter and finishing the year up 201%. The company is the world's largest producer of potash and is benefiting from the positive impact higher agricultural prices are having on fertilizer prices. Contract drilling companies Atwood Oceanics and Diamond Offshore also posted strong gains in the quarter and year on strong demand for their services. Atwood gained 31% in the quarter and was up over 104% for the year while Diamond Offshore gained 27% in the fourth quarter and finished the year up 43%. Other big winners for the year included exchange operators Hong Kong Exchanges and Clearing, up more than 160%, and Singapore Exchange, up 152%. While Hong Kong Exchanges an d Clearing gave back some gains in the fourth quarter, both stocks benefited from very strong trading volumes throughout the year.

On the downside, new position Uranium One was off 29% for the annual period due to a setback in the startup of one of its uranium mines in Kazakhstan. China Shipping Development, China's dominant shipper of oil and coal, fell 19% in the quarter (but was up 3% for the year) due to global concerns about falling shipping rates. The company, however, has continued to report earnings upgrades due to shipping rate increases in China. Japan's Ibiden, a manufacturer of electronic parts and ceramics, fell 18% in the quarter on global recession worries, but the stock ended the year up 37%. Japanese real estate investment manager Kenedix had the largest 12-month dollar loss, falling 30% due to rising interest rates in Japan and concerns that real estate will suffer. Irish beverage company C&C Group fell 19% in the Fund before we sold it. Company earnings and sales declined due to increased competition and poor summer weather.

Global equity markets are entering an interesting and potentially volatile period as the United States works through its significant financial problems and enters what appears to be a much slower period of economic growth. We believe that this will impact economies and companies around the world. While this may mean additional risks for investors, we believe it may also give us additional opportunities to pick up some very good companies at compelling prices.

International investments involve greater potential risks, including less or different regulation, currency fluctuations, economic instability and political developments. Investments in small- and mid-cap companies may be subject to greater volatility and price fluctuations because they may be thinly traded and less liquid. Investing in emerging markets may involve greater risks than investing in more developed countries.

12

Columbia Acorn International Select (ACFFX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Class Z)

through December 31, 2007

Inception 11/23/98	1 year			5 years			Life of fund
Returns before taxes		21.86	%		27.65	%		14.90	%
Returns after taxes on distributions		20.81			27.46			14.74
Returns after taxes on distributions and sale of fund shares		15.74			24.92			13.47
S&P/Citigroup World ex-US Cap Range $2-10B (pretax)		9.84			25.94			12.48

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the additional tax impact of long-term gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class Z shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes.

The Fund's Class Z shares annual operating expense ratio, as stated in the current prospectus, is 1.28%.

Columbia Acorn International Select Portfolio Diversification

as a % of net assets as of 12/31/07

Columbia Acorn International Select Top 10 Holdings

as a % of net assets as of 12/31/07

1.	Fugro (Netherlands) Oilfield Services	4.7%
2.	Nintendo (Japan) Entertainment Software & Hardware	3.6%
3.	SES Global (France) Satellite Broadcasting Services	3.5%
4.	Potash Corp. of Saskatchewan (Canada) World's Largest Producer of Potash	3.1%
5.	Diamond Offshore (United States) Contract Driller	3.1%
6.	Hexagon (Sweden) Measurement Equipment & Polymers	2.9%
7.	Lenovo Group (China) Third Largest PC Vendor Globally	2.7%
8.	Sino Gold (Australia) Gold Mining in The People's Republic of China	2.7%
9.	Smith & Nephew (United Kingdom) Medical Equipment & Supplies	2.7%
10.	Impala Platinum Holdings (South Africa) Platinum Group Metals Mining & Refining	2.7%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn International Select (Class Z)

November 23, 1998 through December 31, 2007

This graph compares the results of $10,000 invested in Columbia Acorn International Select at inception on November 23, 1998 to the S&P/Citigroup World ex-US Cap Range $2-10B. The index and Fund returns include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $277.0 million

13

Columbia Acorn Select

In a Nutshell

Ben Andrews

Lead Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end performance updates.

Fund's Positions

in Mentioned Holdings

as of 12/31/07

Cardtronics	0.7	%
Knoll	0.7	%
American Reprographics	0.5	%
VisionChina Media	0.5	%
Bovespa	0.4	%

Portfolio holdings are subject to change periodically and may not be representative of current characteristics and holdings.

Columbia Acorn Select declined 5.24% in the fourth quarter. This compares to approximately 3% declines for the S&P MidCap 400 and S&P 500 indexes during the quarter. In 2007, the Fund was up 9.20% vs. a gain of 7.98% for the S&P MidCap 400 and a 5.49% increase for the S&P 500. I am pleased that the Fund beat its benchmark for the year.

At the writing of this commentary, we have entered the first quarter of 2008 and many believe the United States has already slipped into a recession. As we look back on the carnage that concluded by the end of the second week in January, a lot of small- and mid-cap stocks have already lost 40% of their value in the last six months. We may be early on in the recession (time wise) but the destruction of capital has already been significant. Therefore, I believe the market may already reflect a large amount of the capital losses that we'll see with this current recession. I put a handful of what I believe to be turnaround candidates in the portfolio in the first half of 2007. These stocks were fairly washed out upon purchase and were taking steps that I believed would improve their fundamentals. In theory, the return to growth for these companies should be counter cyclical to the U.S. economy's woes. So far their improvements have not been meaningful and their shares have continued to decline. This was not the idea but in reviewing these positions, I am more excited by the changes taking place at these companies now than I was when I bought them. If this pattern of improvement can continue, which I believe it will, then these stocks could give us the desired effect in a sluggish economic environment. If not, the holdings may be replaced.

During the fourth quarter, we added five new names while removing one. We exited the Fund's position in Liberty Global during the quarter due to its increased valuation and our concern that its European franchise will experience greater competition than we previously believed. The five added companies were Knoll, Bovespa, VisionChina Media, Cardtronics, and American Reprographics. We took advantage of market chaos at the end of the year to purchase two of these stocks in IPOs at lower than the initial offering price. The price for VisionChina was set at $11 but that didn't generate enough interest from nervous investors so we were able to reset the price with a bid of $8. Cardtronics was initially offered at $10 and instantly collapsed below the offering. The underwriter then spent all morning buying back stock in an attempt to defend the deal. Our traders went to them in the afternoon and bid $8⁵/₈ for 25% of the deal, thus eliminating the over supply of accounts that just wanted to flip the stock. We believe a purchase at this level may reward our shareholders over the coming quarters. VisionChina Media uses real-time mobile digital television broadcast to deliver content and advertising on mass transportation systems in China. Cardtronics owns and manages the largest fleet of ATM machines worldwide.

The subprime crisis allowed us to purchase a couple of companies at discounted prices that we believe won't be significantly damaged by the current market turmoil. They included office interiors and office furniture systems manufacturer Knoll and American Reprographics. American Reprographics is the largest provider of document management services to the architectural, engineering and construction industries and its stock had fallen 50% in the last six months of 2007. The fifth and final new name was Bovespa, the owner of the Sao Paulo stock exchange.

Risks include stock market fluctuations due to economic and business developments. The Fund also has potentially greater price volatility due to the Fund's concentration in a limited number of stocks of mid-size companies. The Fund is a non-diversified fund and may, therefore, have a greater risk of loss from a few issuers than a similar fund that invests more broadly. The Fund may not operate as a nondiversified fund at all times. International investments involve greater potential risks, including less regulation, currency fluctuations, economic instability and political developments.

14

Columbia Acorn Select (ACTWX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Class Z)

through December 31, 2007

Inception 11/23/98	1 year			5 years			Life of fund
Returns before taxes		9.20	%		17.59	%		14.61	%
Returns after taxes on distributions		8.84			17.21			14.11
Returns after taxes on distributions and sale of fund shares		6.46			15.49			12.93
S&P MidCap 400 (pretax)		7.98			16.20			11.50

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the additional tax impact of long-term gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class Z shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes.

The Fund's Class Z shares annual operating expense ratio, as stated in the current prospectus, is 0.98%.

Columbia Acorn Select Portfolio Diversification

as a % of net assets as of 12/31/07

Columbia Acorn Select Top 10 Holdings

as a % of net assets as of 12/31/07

1.	Potash Corp. of Saskatchewan (Canada) World's Largest Producer of Potash	6.4%
2.	Uranium One (South Africa) Uranium Mines in South Africa, Kazakhstan, Australia & the U.S.	5.2%
3.	Janus Capital Group Manages Mutual Funds	4.4%
4.	Abercrombie & Fitch Teen Apparel Retailer	4.3%
5.	Conseco Life, Long-term Care & Medical Supplement Insurance	3.9%
6.	Safeway Supermarkets	3.9%
7.	Expedia Online Travel Services Company	3.6%
8.	Tellabs Telecommunications Equipment	3.6%
9.	ITT Educational Services Post-secondary Degree Services	3.6%
10.	American Tower Communications Towers in USA & Mexico	3.2%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $100,000 Investment in Columbia Acorn Select (Class Z)

November 23, 1998 through December 31, 2007

This graph compares the results of $100,000 invested in Columbia Acorn Select at inception on November 23, 1998 to the S&P MidCap 400. The index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $3.0 billion

15

Columbia Thermostat Fund

In a Nutshell

Charles P. McQuaid

Lead Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Visit columbiamanagement.com for daily and most recent month-end performance updates.

A "fund of fund" bears its allocable share of the costs and expenses of the underlying funds in which it invests. Such funds are thus subject to two levels of fees and potentially higher expense ratios than would be associated with a fund that invests and trades directly in financial instruments under the direction of a single manager.

Columbia Thermostat Fund ended the fourth quarter up 0.35%. This compares to a 3.33% drop in the S&P 500 Index and a 2.17% gain for the Lehman Brothers U.S. Credit Intermediate Bond Index. In 2007, Columbia Thermostat gained 8.49%, topping the S&P 500, up 5.49%, and the Lehman Brothers U.S. Credit Intermediate Bond Index, up 5.60%.

As the table illustrates, all of Columbia Thermostat's equity funds fell in the fourth quarter, resulting in a weighted loss of 2.86%. Bond returns softened the fall with a 1.68% gain. For the year, equities returned 9.22% while the bond component posted a 4.57% return.

Two changes were made to the Fund. Effective December 27, Columbia Federal Securities Fund was replaced with Columbia U.S. Treasury Index Fund. This new fund provides a lower cost fixed income investment choice.

We also revised the Fund's S&P 500 allocation table. In order to better reflect corporate earnings growth, the change adds equity and reduces bond exposures. Because the Fund does not reverse reallocations within 31 days, the change was fortuitously delayed during a time of market weakness. The reallocation was implemented on January 14, 2008, when the Fund hiked stock positions to 60% from 35%.

The credit crunch and housing woes dealt a tough blow to the markets in late 2007. Recession worries have since grown, contributing to volatility. Columbia Thermostat Fund is designed to use these bumps in the market to its advantage, keeping a portion of your invested dollars at an even temperature.

Results of the Funds Owned in Columbia Thermostat Fund

at December 31, 2007

Equities Fund	Weightings in Category			4th quarter returns			1-year returns to 12/31/07
Columbia Acorn Fund		15	%		-3.22	%		7.69	%
Columbia Acorn Select		10	%		-5.24	%		9.20	%
Columbia Marsico Growth Fund		15	%		-0.47	%		14.19	%
Columbia Acorn International		15	%		-2.01	%		17.28	%
Columbia Dividend Income Fund		20	%		-2.99	%		6.94	%
Columbia Large Cap Enhanced Core Fund		25	%		-3.66	%		4.05	%
Weighted Average Equity Return/Loss					-2.86	%		9.22	%
Fixed Income Fund	Weightings in Category			4th quarter returns			1-year returns to 12/31/07
Columbia Intermediate Bond Fund		50	%		1.68	%		4.62	%
Columbia U.S. Treasury Index Fund*		30	%		3.93	%		8.78	%
Columbia Federal Securities Fund*		0	%		3.31	%		5.97	%
Columbia Conservative High Yield Fund		20	%		-0.69	%		2.35	%
Weighted Average Income Return					1.68	%		4.57	%

*Effective December 27, 2007, Columbia Federal Securities Fund was replaced with Columbia U.S. Treasury Index Fund. The weighted average income return reflects the performance of both funds for the period owned.

Columbia Thermostat Fund
Rebalancing in the Fourth Quarter

October 8, 2007:	25% stock, 75% bond
November 8, 2007:	35% stock, 65% bond
November 13, 2007:	40% stock, 60% bond
December 14, 2007:	35% stock, 65% bond

The value of an investment in the Fund is based primarily on the performance of the underlying portfolio funds and the allocation of the Fund's assets among them. An investment in the underlying funds may present certain risks, including stock market fluctuations that occur in response to economic and business developments; and a greater degree of social, political and economic volatility associated with international investing. Small- and mid-cap stocks are often more volatile and less liquid than the stocks of larger companies. Small companies may have a shorter history of operations than larger companies and may have a less diversified product line, making them more susceptible to market pressure. International investments involve greater potential risks, including less or different regulation, currency fluctuations, economic instability and political developments. Changes in interest rates and changes in the financial str ength of issuers of lower-rated bonds may also affect underlying fund performance. The Fund is also subject to the risk that the investment adviser's decisions regarding asset classes and portfolio funds will not anticipate market trends successfully, resulting in a failure to preserve capital or lower total return. In addition, the Fund may buy and sell shares of the portfolio funds frequently. This may result in higher transaction costs and additional tax liability. This is not an offer of the shares of any other mutual fund mentioned herein.

16

Columbia Thermostat Fund (COTZX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Class Z)

through December 31, 2007

Inception 9/25/02	1 year			5 year			Life of fund
Returns before taxes		8.49	%		10.66	%		10.93	%
Returns after taxes on distributions		5.31			8.78			9.15
Returns after taxes on distributions and sale of fund shares		6.21			8.42			8.72
S&P 500 (pretax)		5.49			12.83			13.78
Lehman Brothers U.S. Credit Intermediate Bond Index (pretax)		5.60			4.49			4.85
Lipper Flexible Portfolio Funds Index (pretax)		9.57			12.10			12.65

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the additional tax impact of long-term gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class Z shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes.

The Fund's annual operating expense ratio, as stated in the current prospectus, reflects a contractual expense waiver or reimbursement that expires April 30, 2008. Expense ratios for Class Z shares without and with the contractual waiver, including fees and expenses associated with the Fund's investment in other investment companies, are 1.10% and 0.94%, respectively. Absent the waiver or reimbursement, performance results would have been lower.

Columbia Thermostat Fund Asset Allocation

as a % of net assets as of 12/31/07

Columbia Thermostat Fund Portfolio Weightings

as a % of assets in each investment category as of 12/31/07

Stock Mutual Funds

Columbia Large Cap Enhanced Core Fund	25	%
Columbia Dividend Income Fund	20	%
Columbia Acorn Fund	15	%
Columbia Acorn International	15	%
Columbia Marsico Growth Fund	15	%
Columbia Acorn Select	10	%

Bond Mutual Funds

Columbia Intermediate Bond Fund	50	%
Columbia U.S. Treasury Index Fund	30	%
Columbia Conservative High Yield Fund	20	%

The Growth of a $10,000 Investment in Columbia Thermostat Fund (Class Z)

September 25, 2002 through December 31, 2007

This graph compares the results of $10,000 invested in Columbia Thermostat Fund at inception on September 25, 2002 to the S&P 500, the Lehman Brothers U.S. Credit Intermediate Bond Index and the Lipper Flexible Portfolio Funds Index. The indexes are unmanaged and returns for the indexes and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $183.5 million

17

Columbia Acorn Fund

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	09/30/07		12/31/07
Additions
Information
AMIS Holdings		3,355,000		3,782,000
Blackbaud		1,326,000		1,800,000
Ciena		370,000		540,000
Cogent Communications		2,000,000		2,836,000
Dolby Laboratories		924,000		1,150,000
Epicor		2,500,000		3,500,000
FARO Technologies		860,000		1,044,000
General Communications		0		2,241,000
II-VI		2,257,000		2,400,000
Informatica		4,000,000		4,095,000
IPG Photonics		1,237,000		1,800,000
Jupiter Telecommunications (Japan)		70,000		88,000
Kenexa		1,868,000		2,425,000
Mediacom Communications		1,250,000		1,500,000
MetroPCS Communications		175,000		1,000,000
Netgear		932,000		1,110,000
Polycom		1,665,000		1,840,000
Quality Systems		0		1,510,000
Red Hat		1,600,000		3,000,000
Sanmina-SCI		26,000,000		29,500,000
Scientific Games		2,850,000		3,000,000
SRA International		1,050,000		1,150,000
Stratasys		650,000		775,000
Supertex		820,000		900,000
Switch & Data Facilities		900,000		2,000,000
Teradata		0		1,290,000
THQ		2,000,000		2,200,000
Time Warner Telecom		6,500,000		8,000,000
VeriFone Holdings		0		450,000
Viad		461,000		1,453,000
VisionChina Media (China)		0		1,250,000
Industrial Goods & Services
Acuity Brands		0		701,000
Administaff		1,900,000		2,025,000
Albany International		1,050,000		1,260,000
Allied Waste Industries		0		2,200,000
Aptargroup		146,000		300,000
Cytec Industries		400,000		500,000
Greif		400,000		600,000
Interline Brands		1,200,000		1,700,000
Kaydon		1,300,000		1,696,000
Martin Marietta Materials		650,000		750,000
MOOG		196,000		573,000
Oshkosh Truck		0		900,000
Texas Industries		0		450,000
Toro		833,000		1,100,000
TrueBlue		0		2,300,000

	Number of Shares
	09/30/07		12/31/07
Industrial Goods & Services—continued
Vulcan Materials		325,000		775,000
Wavin (Netherlands)		611,460		622,187
Zumtobel (Austria)		500,000		750,000
Consumer Goods & Services
American Woodmark		0		600,000
Choice Hotels		425,000		1,300,000
Church & Dwight		126,000		161,000
Fleetwood Enterprises		765,000		1,765,000
Pinnacle Entertainment		3,850,000		4,050,000
Smart Balance		0		1,500,000
Thor Industries		785,000		1,050,000
Winnebago		390,000		640,000
Finance
Aaron Rents		0		250,000
Bovespa (Brazil)		0		1,181,800
CAI International		1,200,000		1,500,000
Cohen & Steers		100,000		400,000
Conseco		5,950,000		6,500,000
Delphi Financial Group		1,000,000		1,600,000
GATX		520,000		771,000
H & E Equipment Services		300,000		600,000
KBW		350,000		550,000
MB Financial		920,000		1,240,000
Stewart Information Services		0		500,000
TriCo Bancshares		650,000		900,000
Valley National Bancorp		0		643,000
Energy & Minerals
Carrizo Oil & Gas		1,300,000		1,656,000
Dresser-Rand Group		1,448,000		1,675,000
Pacific Stratus Energy (Canada)		0		1,300,000
Petro Rubiales Energy (Canada)		0		15,000,000
SBM Offshore (Netherlands)		550,000		640,200
ShawCor (Canada)		1,183,100		1,283,100
Tesco		1,640,000		1,804,000
Health Care
Alexion Pharmaceuticals		0		655,000
Arena Pharmaceuticals		2,020,000		2,500,000
Array Biopharma		2,160,000		2,660,000
Cephalon		1,050,000		1,115,000
Charles River Laboratories		1,085,000		1,245,000
Haemonetics		578,000		700,000
Henry Schein		929,000		1,090,000
Hologic		0		1,648,000
Illumina		225,000		725,000
Kinetic Concepts		0		435,000

See accompanying notes to financial statements.

18

	Number of Shares
	09/30/07		12/31/07
Additions (continued)
Health Care—continued
Medarex		2,000,000		2,550,000
MGI Pharma		1,010,000		1,090,000
Neurogen		2,190,000		2,300,000
Orthofix International		943,000		1,330,000
Pharmacopeia		825,000		1,675,000
QIAGEN (Netherlands)		1,250,000		1,775,000
Other Industries
BioMed Realty Trust		0		1,000,000
Federal Realty Investment Trust		575,000		860,000
Heartland Express		2,264,000		3,000,000
JB Hunt Transport Services		2,000,000		3,000,000
Jiangsu Expressway (China)		20,000,000		38,000,000
Rush Enterprises		0		956,000
Sales
Information
Actuate		5,306,000		5,000,000
Ceridian		3,000,000		0
CTS		1,310,000		631,000
Diebold		225,000		0
Dobson Communications		4,000,000		0
Hong Kong Exchanges and Clearing (Hong Kong)		6,500,000		3,300,000
Liberty Global, Series A		1,500,000		0
Liberty Global, Series C		2,050,000		1,500,000
Rogers		503,000		395,000
Singapore Exchange (Singapore)		5,000,000		4,000,000
Wincor Nixdorf (Germany)		570,000		460,000
Windstream		1,000,000		0
Industrial Goods & Services
Carbone Lorraine (France)		400,000		334,000
Florida Rock		1,900,000		0
Geberit (Switzerland)		170,000		0
Genlyte Group		2,600,000		950,000
Kingspan Group (Ireland)		444,400		413,100
Labor Ready		2,300,000		0
Neopost (France)		112,000		0
Spartech		1,050,000		0
USG People (Netherlands)		750,000		435,000
UTI Worldwide		2,700,000		2,500,000
Worthington Industries		320,000		0
Consumer Goods & Services
Carter's		918,000		0
Chico's FAS		9,130,000		7,600,000
Christopher & Banks		3,743,000		2,800,000
Hansen Natural		1,800,000		1,600,000
Natura Cosmeticos		1,100,000		0

	Number of Shares
	09/30/07		12/31/07
Consumer Goods & Services—continued
Nobia (Sweden)		2,960,000		0
Station Casinos		400,000		0
Finance
Eaton Vance		5,250,000		4,805,000
Great Southern Bancorp		636,000		614,000
Greene County Bancshares		150,000		135,000
Housing Development Finance (India)		1,700,000		1,350,000
Nuveen Investments		1,303,000		0
TCF Financial		2,156,000		1,800,000
United America Indemnity		1,550,000		0
Energy & Minerals
Aracruz Celulose		550,000		0
CARBO Ceramics		750,000		706,000
Key Energy Services		170,000		0
Rowan		1,161,000		600,000
St. Mary Land & Exploration		300,000		100,000
Talisman Energy (Canada)		4,900,000		4,000,000
Tullow Oil (United Kingdom)		9,315,000		4,629,000
Health Care
Arrow International		905,000		0
Coventry Health Care		500,000		0
Cytyc		2,102,000		0
Dade Behring		550,000		0
Endo Pharmaceuticals		1,300,000		0
La Jolla Pharmaceutical		359,000		97,000
LCA-Vision		1,125,000		0
Lexicon Genetics		3,100,000		2,035,000
Myriad Genetics		650,000		550,000
Nobel Biocare Holding (Switzerland)		75,000		0
Polymedica		1,025,000		0
Rhoen-Klinikum (Germany)		2,000,000		1,650,000
Synthes (Switzerland)		315,000		0
Other Industries
Brandywine Realty		1,020,000		0
China Shipping Development (China)		14,120,000		7,820,000

See accompanying notes to financial statements.

19

Columbia Acorn Fund

Statement of Investments, December 31, 2007

Number of Shares			Value (000)
				Equities: 95.9%
Information 26.2%
		> Business Software 3.9%
	1,400,000	Micros Systems (a)	$	98,224
		Information Systems for Restaurants & Hotels
	12,400,000	Novell (a)		85,188
		Directory, Operating System & Identity Management Software
	4,095,000	Informatica (a)		73,792
		Enterprise Data Integration Software
	3,000,000	Red Hat (a)		62,520
		Maintenance & Support for Opensource
	1,800,000	Avid Technology (a)		51,012
		Digital Nonlinear Editing Software & Systems
	1,400,000	Concur Technologies (a)		50,694
		Web Enabled Cost & Expense Management Software
	1,800,000	Blackbaud		50,472
		Software & Services for Non-profits
	2,425,000	Kenexa (a)(b)		47,094
		Recruiting & Workforce Management Solutions
	1,510,000	Quality Systems (b)		46,040
		IT Systems for Medical Groups & Ambulatory Care Centers
	2,500,000	Radiant Systems (a)(b)		43,075
		Point of Sale Systems: Convenient Stores & Restaurants
	1,007,000	ANSYS (a)		41,750
		Simulation Software for Engineers & Designers
	3,500,000	Epicor (a)(b)		41,230
		Software Systems to Run Small Businesses
	5,000,000	Actuate (a)(b)		38,850
		Information Delivery Software & Solutions
	1,800,000	Parametric Technology (a)		32,130
		Engineering Software & Services
	1,000,000	Cadence Design Systems (a)		17,010
		Electronic Design Automation Software
				779,081
		> Computer Hardware & Related Equipment 3.6%
	3,800,000	Amphenol		176,206
		Electronic Connectors
	2,280,000	Belden CDT (b)		101,460
		Specialty Cable
	2,400,000	II-VI (a)(b)		73,320
		Laser Components
	1,150,000	Dolby Laboratories (a)		57,178
		Audio Technology for Consumer Electronics
	1,426,000	Nice Systems (Israel) (a)		48,940
		Audio & Video Recording Solutions
	460,000	Wincor Nixdorf (Germany)		43,350
		Retail POS Systems & ATM Machines
	1,110,000	Netgear (a)		39,594
		Networking Products for Small Business & Home
	1,290,000	Teradata (a)		35,359
		Enterprise Data Warehouse Systems
	945,000	Zebra Technologies (a)		32,791
		Bar Code Printers

Number of Shares			Value (000)
	1,027,000	Avocent (a)	$	23,939
		Computer Control Switches
	775,000	Stratasys (a)		20,026
		Rapid Prototyping Systems
	735,000	Excel Technology (a)(b)		19,918
		Laser Systems & Electro-optical Components
	395,000	Rogers (a)		17,131
		PCB Laminates & High-performance Foams
	450,000	VeriFone Holdings (a)		10,463
		Point of Sale Systems
	500,000	Intermec (a)		10,155
		Bar Code & Wireless LAN Systems
	631,000	CTS		6,266
		Electronic Components, Sensors & Electronics Manufacturing Solutions
				716,096
		> Instrumentation 2.6%
	5,600,000	Flir Systems (a)		175,280
		Infrared Cameras
	3,070,000	Trimble Navigation (a)		92,837
		GPS-based Instruments
	750,000	Mettler Toledo (a)		85,350
		Laboratory Equipment
	800,000	Varian (a)		52,240
		Analytical Instruments
	600,000	Dionex (a)		49,716
		Ion & Liquid Chromatography
	1,800,000	IPG Photonics (a)		35,982
		Fiber Lasers
	1,044,000	FARO Technologies (a)(b)		28,376
		Precision Measurement Equipment
				519,781
		> Gaming Equipment & Services 2.0%
	3,150,000	Bally Technologies (a)(b)		156,618
		Slot Machines & Software
	2,750,000	International Game Technology		120,807
		Slot Machines & Progressive Slots
	3,000,000	Scientific Games (a)		99,750
		Lottery Services Provider
	2,430,000	Shuffle Master (a)(b)		29,136
		Card Shufflers & Casino Games
				406,311
		> Mobile Communications 2.0%
	4,500,000	Crown Castle International (a)		187,200
		Communications Towers
	3,500,000	American Tower (a)		149,100
		Communications Towers in USA & Mexico
	600,000	Telephone & Data Systems		37,560
		Cellular & Wireline Telephone Services
	1,000,000	MetroPCS Communications (a)		19,450
		Discount Cellular Telephone Services
	600,000	Globalstar (a)		4,800
		Satellite Mobile Voice & Data Carrier
				398,110
		> Internet Related 1.6%
	9,500,000	SkillSoft (a)(b)		90,820
		Web-based Learning Solutions (E-Learning)

See accompanying notes to financial statements.

20

Number of Shares			Value (000)
		> Internet Related—continued
	3,000,000	ValueClick (a)	$	65,700
		Internet Advertising
	700,000	Sohu.com (China) (a)		38,164
		Advertising on Chinese Internet Portal
	4,000,000	CNET Networks (a)		36,560
		Internet Advertising on Niche Websites
	2,000,000	Switch & Data Facilities (a)(b)		32,040
		Network Neutral Data Centers
	225,000	Equinix (a)		22,741
		Network Neutral Data Centers
	1,400,000	TheStreet.com		22,288
		Financial Information Website Publisher
	1,700,000	Marchex (b)		18,462
		Internet Advertising
				326,775
		> Semiconductors & Related Equipment 1.4%
	4,800,000	Integrated Device Technology (a)		54,288
		Communications Semiconductors
	2,250,000	Microsemi (a)		49,815
		Analog/Mixed-signal Semiconductors
	1,420,000	Littelfuse (a)(b)		46,803
		Little Fuses
	3,782,000	AMIS Holdings (a)		37,896
		Mixed-signal Semiconductors
	900,000	Supertex (a)(b)		28,161
		Mixed-signal Semiconductors
	3,000,000	Entegris (a)		25,890
		Semiconductor Wafer Shipping & Handling Products
	6,591,493	Everlight Electronics (Taiwan)		23,983
		Led Packager
	1,905,000	IXYS (a)(b)		15,278
		Power Semiconductors
				282,114
		> CATV 1.3%
	4,500,000	Discovery Holding (a)		113,130
		CATV Programming
	88,000	Jupiter Telecommunications (Japan) (a)		74,443
		Largest Cable Service Provider in Japan
	1,500,000	Liberty Global, Series C (a)		54,885
		Cable TV Franchises outside the USA
	130,000	Liberty Media Corp - Capital (a)		15,144
		CATV Holding Company
	1,500,000	Mediacom Communications (a)		6,885
		Cable Television Franchises
				264,487
		> Financial Processors 1.3%
	2,774,000	Global Payments		129,046
		Credit Card Processor
	3,300,000	Hong Kong Exchanges and Clearing (Hong Kong)		92,641
		Hong Kong Equity & Derivatives Market Operator
	4,000,000	Singapore Exchange (Singapore)		36,564
		Singapore Equity & Derivatives Market Operator
				258,251

Number of Shares			Value (000)
		> Telephone Services 1.2%
	8,000,000	Time Warner Telecom (a)(b)	$	162,320
		Fiber Optic Telephone/Data Services
	2,836,000	Cogent Communications (a)(b)		67,241
		Internet Data Pipelines
	2,241,000	General Communications (a)		19,609
		CATV, Web, Phone & Commercial Communications Provider in Alaska
				249,170
		> Telecommunications Equipment 0.9%
	15,600,000	Tellabs (a)		102,024
		Telecommunications Equipment
	1,840,000	Polycom (a)		51,115
		Video Conferencing Equipment
	540,000	Ciena (a)		18,420
		Optical Transport & Broadband Access Equipment
				171,559
		> Business Information & Marketing Services 0.7%
	1,453,000	Viad (b)		45,886
		Trade Show Services, Travel & Tours
	2,500,000	Navigant Consulting (a)(b)		34,175
		Financial Consulting Firm
	420,000	FTI Consulting (a)		25,889
		Financial Consulting Firm
	2,000,000	Voyager Learning (a)(b)		14,300
		Education Services for the K-12 Market
	2,500,000	Taylor Nelson Sofres (United Kingdom)		10,244
		Market Research
	250,000	Getty Images (a)		7,250
		Photographs for Publications & Electronic Media
	800,000	infoUSA		7,144
		Business Data for Sales Leads
				144,888
		> Publishing 0.6%
	1,200,000	NAVTEQ (a)		90,720
		Map Data for Electronic Devices
	800,000	Prisa (Spain)		14,875
		Leading Spanish-speaking Publisher
	1,300,000	Informa Group (United Kingdom)		11,891
		Global Publisher & Event Organizer
				117,486
		> Electronics Distribution 0.6%
	2,840,000	Avnet (a)		99,315
		Electronic Components Distribution
	710,000	Agilysys		10,735
		IT Distributor
				110,050
		> Contract Manufacturing 0.5%
	29,500,000	Sanmina-SCI (a)(b)		53,690
		Electronic Manufacturing Services
	1,475,000	Plexus (a)		38,734
		Electronic Manufacturing Services
	690,000	Jabil Circuit		10,536
		Electronic Manufacturing Services
				102,960

See accompanying notes to financial statements.

21

Columbia Acorn Fund

Statement of Investments, continued

Number of Shares			Value (000)
		> Computer Services 0.5%
	5,000,000	iGate (a)(b)	$	42,350
		IT & Business Process Outsourcing Services
	1,150,000	SRA International (a)		33,867
		Government IT Services
	4,600,000	AnswerThink (a)(b)		22,264
		IT Integration & Best Practice Research
				98,481
		> Consumer Software 0.4%
	2,200,000	THQ (a)		62,018
		Entertainment Software
	750,000	Activision (a)		22,275
		Entertainment Software
				84,293
		> Satellite Broadcasting & Services 0.4%
	2,755,000	SES Global (France)		72,241
		Satellite Broadcasting Services
				72,241
		> Television Programming 0.2%
	4,000,000	Lions Gate Entertainment (a)		37,680
		Film & TV Studio
				37,680
		> Radio 0.2%
	1,500,000	Cumulus Media (a)		12,060
		Radio Stations in Small Cities
	1,541,000	Salem Communications (b)		10,155
		Radio Stations for Religious Programming
	1,400,000	Saga Communications (a)(b)		8,246
		Radio Stations in Small- & Mid-sized Cities
	2,400,000	Spanish Broadcasting System (a)(b)		4,440
		Spanish Language Radio Stations
				34,901
		> TV Broadcasting 0.2%
	2,500,000	Entravision Communications (a)		19,575
		Spanish Language TV, Radio & Outdoor
	1,750,000	Gray Television		14,035
		Mid Market Affiliated TV Stations
				33,610
		> Advertising 0.1%
	1,250,000	VisionChina Media (China) (a)		10,625
		Advertising on Digital Screens in China's Mass Transit System
				10,625
Information: Total				5,218,950
Industrial Goods & Services 17.8%
		> Machinery 6.5%
	5,000,000	Ametek		234,200
		Aerospace/Industrial Instruments
	4,200,000	Donaldson (b)		194,796
		Industrial Air Filtration
	3,500,000	Clarcor (b)		132,895
		Mobile & Industrial Filters
	2,850,000	Pentair		99,209
		Pumps & Water Treatment

Number of Shares			Value (000)
	1,814,000	Mine Safety Appliances (b)	$	94,092
		Safety Equipment
	1,696,000	Kaydon (b)		92,500
		Specialized Friction & Motion Control Products
	2,250,000	Pall		90,720
		Filtration & Fluids Clarification
	2,200,000	ESCO Technologies (a)(b)		87,868
		Automatic Electric Meter Readers
	1,250,000	Nordson		72,450
		Dispensing Systems for Adhesives & Coatings
	2,700,000	Goodman Global (a)		66,258
		HVAC Equipment Manufacturer
	1,100,000	Toro		59,884
		Turf Maintenance Equipment
	900,000	Oshkosh Truck		42,534
		Specialty Truck Manufacturer
	573,000	MOOG (a)		26,249
		Motion Control Products for Aerospace, Defense & Industrial Markets
	360,000	Union Tool (Japan)		11,907
		Precision Drill Bit Manufacturer
				1,305,562
		> Other Industrial Services 2.9%
	5,500,000	Expeditors International of Washington		245,740
		International Freight Forwarder
	1,900,000	Forward Air (b)		59,223
		Freight Transportation Between Airports
	2,500,000	UTI Worldwide		49,000
		Global Logistics & Freight Forwarding
	2,300,000	TrueBlue (a)(b)		33,304
		Temporary Manual Labor
	2,000,000	American Reprographics (a)		32,960
		Document Management & Logistics
	2,000,000	American Commercial Lines (a)		32,480
		Operator/Builder of Inland Barges
	1,750,000	Mobile Mini (a)(b)		32,445
		Portable Storage Units Leasing
	1,122,000	Imtech (Netherlands)		27,576
		Engineering & Technical Services
	600,000	G&K Services		22,512
		Uniform Rental
	1,100,000	Intertek Testing (United Kingdom)		21,566
		Testing, Inspection, Certification Services
	615,000	TAL International Group		14,004
		Intermodal Freight Containers Leasing
				570,810
		> Industrial Materials & Specialty Chemicals 1.8%
	530,000	Novozymes (Denmark)		59,818
		Industrial Enzymes
	1,260,000	Albany International		46,746
		Paper Machine Clothing & Advanced Textiles
	23,000	Sika (Switzerland)		43,234
		Chemicals for Construction & Industrial Applications
	600,000	Greif		39,222
		Industrial Packaging
	1,378,000	Drew Industries (a)(b)		37,757
		RV & Manufactured Home Components

See accompanying notes to financial statements.

22

Number of Shares			Value (000)
		> Industrial Materials & Specialty Chemicals—continued
	195,000	Sociedad Quimica y Minera de Chile (Chile)	$	34,466
		Producer of Specialty Fertilizers, Lithium & Iodine
	500,000	Cytec Industries		30,790
		Aerospace Composites & Specialty Chemical
	334,000	Carbone Lorraine (France)		23,015
		Advanced Industrial Materials
	2,850,000	Kansai Paint (Japan)		20,673
		Paint Producer in Japan, India, China & Southeast Asia
	441,384	Koninklijke TenCate (Netherlands)		13,644
		Advanced Textiles & Industrial Fabrics
	300,000	Aptargroup		12,273
		Dispensing Systems for Consumer Products & Pharmaceuticals
	622,187	Wavin (Netherlands)		8,230
		Largest European Plastic Pipe Systems Company
				369,868
		> Industrial Distribution 1.7%
	1,300,000	WW Grainger		113,776
		Industrial Distribution
	1,925,000	Airgas		100,312
		Industrial Gas Distributor
	2,375,000	Watsco (b)		87,305
		HVAC Distribution
	1,700,000	Interline Brands (a)(b)		37,247
		Industrial Distribution
				338,640
		> Construction 1.3%
	750,000	Martin Marietta Materials		99,450
		Aggregates
	775,000	Vulcan Materials		61,294
		Aggregates, Concrete & Asphalt
	2,200,000	Simpson Manufacturing		58,498
		Wall Joint Maker
	450,000	Texas Industries		31,545
		Aggregates, Cement & Concrete
	413,100	Kingspan Group (Ireland)		6,226
		Building Insulation & Environmental Containers
				257,013
		> Electrical Components 1.0%
	950,000	Genlyte Group (a)		90,440
		Commercial Lighting Fixtures
	701,000	Acuity Brands		31,545
		Commercial Lighting Fixtures
	750,000	Zumtobel (Austria)		26,921
		Lighting Systems
	1,125,000	Ushio (Japan)		24,692
		Industrial Light Sources
	700,000	Legrand (France)		23,776
		Electrical Components
				197,374
		> Conglomerates 1.0%
	4,845,000	Hexagon (Sweden)		99,911
		Measurement Equipment & Polymers

Number of Shares			Value (000)
	2,758,309	Aalberts Industries (Netherlands)	$	54,367
		Flow Control & Heat Treatment
	600,000	Ibiden (Japan)		41,443
		Electronic Parts & Ceramics
				195,721
		> Outsourcing Services 0.7%
	2,300,000	Quanta Services (a)		60,352
		Electrical & Telecom Construction Services
	2,025,000	Administaff (b)		57,267
		Professional Employer Organization
	435,000	USG People (Netherlands)		11,661
		Temporary Staffing Services
	600,000	GP Strategies (a)		6,390
		Training Programs
				135,670
		> Waste Management 0.5%
	2,550,000	Waste Connections (a)		78,795
		Solid Waste Management
	2,200,000	Allied Waste Industries (a)		24,244
		Solid Waste Management
				103,039
		> Steel 0.4%
	2,860,000	Gibraltar Industries (b)		44,101
		Steel Processing & Building Products
	135,000	Vallourec (France)		36,343
		Oil, Gas & Industrial Seamless Tubes
				80,444
Industrial Goods & Services: Total				3,554,141
Consumer Goods & Services 15.1%
		> Retail 3.5%
	3,140,000	Abercrombie & Fitch		251,106
		Teen Apparel Retailer
	4,850,000	Urban Outfitters (a)		132,211
		Apparel & Home Specialty Retailer
	1,975,000	J Crew Group (a)		95,214
		Multi-channel Branded Retailer
	7,600,000	Chico's FAS (a)		68,628
		Women's Specialty Retailer
	1,200,000	Gaiam (a)(b)		35,616
		Healthy Living Catalogs & E-Commerce
	2,800,000	Christopher & Banks (b)		32,060
		Women's Apparel Retailer
	1,223,000	AnnTaylor Stores (a)		31,260
		Women's Apparel Retailer
	775,000	Genesco (a)		29,295
		Multi-concept Branded Footwear Retailer
	1,564,000	RONA (Canada) (a)		27,019
		Leading Canadian Do-it-yourself Retailer
	30,000	Lululemon Athletica (a)		1,421
		Premium Active Apparel Retailer
				703,830
		> Other Consumer Services 1.7%
	2,000,000	ITT Educational Services (a)(b)		170,540
		Post-secondary Degree Services

See accompanying notes to financial statements.

23

Columbia Acorn Fund

Statement of Investments, continued

Number of Shares			Value (000)
		> Other Consumer Services—continued
	1,275,000	Weight Watchers International	$	57,604
		Weight Loss Programs
	1,120,000	NutriSystem (a)		30,218
		Weight Loss Programs
	1,500,000	Universal Technical Institute (a)(b)		25,500
		Vocational Training
	2,550,000	Princeton Review (a)(b)		21,242
		College Preparation Courses
	2,100,000	Park24 (Japan)		16,172
		Parking Lot Operator
	110,000	Pierre & Vacances (France)		15,197
		Vacation Apartment Lets
	100,000	Lincoln Technical Institute (a)		1,472
		Vocational Training
				337,945
		> Apparel 1.6%
	7,330,000	Coach (a)		224,152
		Designer & Retailer of Branded Leather Accessories
	3,000,000	Billabong International (Australia)		38,982
		Action Sports Apparel Brand Manager
	1,069,000	Oxford Industries (b)		27,548
		Branded & Private Label Apparel
	900,000	True Religion Apparel (a)		19,215
		Premium Denim
				309,897
		> Travel 1.6%
	2,390,000	Vail Resorts (a)(b)		128,606
		Ski Resort Operator & Developer
	4,000,000	Expedia (a)		126,480
		Online Travel Services Company
	1,300,000	Choice Hotels		43,160
		Franchisor of Budget Hotel Brands
	601,000	Ambassadors Group		11,004
		Educational Student Travel Services
				309,250
		> Nondurables 1.4%
	2,860,000	Scotts Miracle-Gro		107,021
		Consumer Lawn & Garden Products
	1,010,000	Chattem (a)(b)		76,296
		Personal Care Products
	2,500,000	Jarden (a)		59,025
		Branded Household Products
	1,900,000	Helen of Troy (a)(b)		32,566
		Hair Dryers & Curling Irons
	161,000	Church & Dwight		8,705
		Branded Household & Personal Care Products
				283,613
		> Furniture & Textiles 1.3%
	4,000,000	Herman Miller (b)		129,560
		Office Furniture
	2,000,000	HNI		70,120
		Office Furniture & Fireplaces
	3,400,000	Knoll (b)		55,862
		Office Furniture
	600,000	American Woodmark		10,908
		Kitchen Cabinet Manufacturer
				266,450

Number of Shares			Value (000)
		> Casinos & Gaming 1.2%
	1,700,000	Penn National Gaming (a)	$	101,235
		Regional Casino Operator
	4,050,000	Pinnacle Entertainment (a)(b)		95,418
		Regional Casino Operator
	2,380,000	Intralot (Greece)		46,898
		Lottery & Gaming Systems & Services
	226,000	Lakes Entertainment (a)		1,566
		Native American Casinos Development
				245,117
		> Leisure Products 1.0%
	1,416,000	Speedway Motorsports		44,009
		Motorsports Racetrack Owner & Operator
	1,025,000	International Speedway		42,209
		Largest Motorsports Racetrack Owner & Operator
	1,050,000	Thor Industries		39,911
		RV & Bus Manufacturer
	800,000	Harley-Davidson		37,368
		Motorcycles & Related Merchandise
	640,000	Winnebago		13,453
		Premier Motorhome Maker
	5,410,390	Ducati Motor (Italy) (a)		11,056
		Motorcycles & Related Merchandise
	1,765,000	Fleetwood Enterprises (a)		10,555
		RV & Manufactured Home Maker
				198,561
		> Restaurants 0.6%
	2,145,000	Sonic (a)		46,975
		Quick Service Restaurant
	1,000,000	Red Robin Gourmet Burgers (a)(b)		31,990
		Casual Dining Restaurant
	1,150,000	Cheesecake Factory (a)		27,267
		Casual Dining Restaurants
	1,800,000	AFC Enterprises (a)(b)		20,376
		Popeyes Restaurants
				126,608
		> Food & Beverage 0.6%
	1,600,000	Hansen Natural (a)		70,864
		Alternative Beverages
	1,000,000	IAWS Group (Ireland)		22,135
		Baked Goods
	1,500,000	Smart Balance (a)		16,395
		Healthy Food Products
				109,394
		> Consumer Goods Distribution 0.3%
	2,890,000	Pool (b)		57,309
		Distributor of Swimming Pool Supplies & Equipment
				57,309
		> Cruise Lines 0.1%
	400,000	Carnival		17,796
		Largest Cruise Line
				17,796

See accompanying notes to financial statements.

24

Number of Shares			Value (000)
		> Other Entertainment 0.1%
	435,000	CTS Eventim (Germany)	$	16,719
		Event Ticket Sales
				16,719
		> Other Durable Goods 0.1%
	900,000	Champion Enterprises (a)		8,478
		Manufactured Homes
	172,000	Cavco Industries (a)		5,821
		Higher End Manufactured Homes
				14,299
Consumer Goods & Services: Total				2,996,788
Finance 13.0%
		> Insurance 4.2%
	3,965,000	HCC Insurance Holdings		113,716
		Specialty Insurance
	2,390,000	Philadelphia Consolidated Holding (a)		94,047
		Specialty Insurance
	1,748,000	Leucadia National		82,331
		Insurance Holding Company
	6,500,000	Conseco (a)		81,640
		Life, Long-term Care & Medical Supplement Insurance
	1,200,000	Assurant		80,280
		Specialty Insurance
	149,000	Markel (a)		73,174
		Specialty Insurance
	1,600,000	Delphi Financial Group		56,448
		Group Employee Benefit Products & Services
	1,000,000	Endurance Specialty Holdings		41,730
		Commercial Lines Insurance/Reinsurance
	995,000	Protective Life		40,815
		Life Insurance
	740,000	Stancorp Financial Group		37,281
		Group Life & Disability Insurance
	1,420,000	Selective Insurance Group		32,646
		Commercial & Personal Lines Insurance
	1,000,000	Aspen Insurance		28,840
		Commercial Lines Insurance/Reinsurance
	600,000	National Financial Partners		27,366
		Distributor of Life Insurance, Group Benefits & Investment Advisory Services
	2,000,000	Meadowbrook Insurance Group (a)(b)		18,820
		Specialty Insurance Products & Services
	280,000	April Group (France)		18,796
		Insurance Policy Construction
	500,000	Stewart Information Services		13,045
		Title Company
				840,975
		> Banks 3.0%
	3,500,000	BOK Financial (b)		180,950
		Tulsa Based S.W. Bank
	3,511,000	Associated Banc-Corp		95,113
		Midwest Bank
	4,246,000	Glacier Bancorp (b)		79,570
		Mountain States Bank
	1,222,000	Chittenden		43,528
		New England Bank

Number of Shares			Value (000)
	1,240,000	MB Financial	$	38,229
		Chicago Bank
	1,800,000	TCF Financial		32,274
		Great Lakes Bank
	1,437,000	West Coast Bancorp (b)		26,584
		Portland Small Business Bank
	530,000	First Financial Bankshares		19,955
		West Texas Bank
	900,000	TriCo Bancshares (b)		17,370
		California Central Valley Community Bank
	1,312,000	West Bancorporation (b)		17,108
		Des Moines Commercial Bank
	614,000	Great Southern Bancorp		13,483
		Missouri Real Estate Lender
	643,000	Valley National Bancorp		12,256
		New Jersey/New York Bank
	400,000	First Mutual Bancshares (b)		10,572
		Seattle Community Bank
	450,000	First Busey		8,937
		Illinois Bank
	135,000	Greene County Bancshares		2,592
		Tennessee Bank
				598,521
		> Brokerage & Money Management 2.4%
	4,805,000	Eaton Vance		218,195
		Specialty Mutual Funds
	6,168,000	SEI Investments		198,425
		Mutual Fund Administration & Investment Management
	1,181,800	Bovespa (Brazil) (a)		22,773
		Brazil Equity & Derivative Exchange
	450,000	Investment Technology Group (a)		21,415
		Electronic Trading
	550,000	KBW (a)		14,075
		Investment Bank to Financial Industry
	400,000	Cohen & Steers		11,988
		Top REIT Fund Manager
				486,871
		> Savings & Loans 2.0%
	11,585,000	People's United		206,213
		Connecticut Savings & Loan
	1,350,000	Housing Development Finance (India)		96,864
		Indian Mortgage Lender
	2,725,000	Washington Federal		57,525
		Traditional Thrift
	774,000	Anchor Bancorp Wisconsin		18,204
		Wisconsin Thrift
	200,000	Downey Financial		6,222
		Option Arm Lender
	360,000	Provident New York Bancorp		4,651
		New York State Thrift
				389,679
		> Finance Companies 1.4%
	7,235,000	AmeriCredit (a)(b)		92,536
		Auto Lending
	1,675,000	World Acceptance (a)(b)		45,191
		Personal Loans
	1,700,000	McGrath Rentcorp (b)		43,775
		Temporary Space & IT Rentals

See accompanying notes to financial statements.

25

Columbia Acorn Fund

Statement of Investments, continued

Number of Shares			Value (000)
		> Finance Companies—continued
	771,000	GATX	$	28,280
		Rail Car Lessor
	1,500,000	CAI International (a)(b)		15,780
		International Container Leasing & Management
	1,100,000	Marlin Business Services (a)(b)		13,266
		Small Equipment Leasing
	850,000	Electro Rent		12,623
		Test & Measurement Rentals
	600,000	H & E Equipment Services (a)		11,328
		Heavy Equipment Leasing
	500,000	Rent-A-Center (a)		7,260
		Rent to Own
	250,000	Aaron Rents		4,810
		Rent to Own
				274,849
Finance: Total				2,590,895
Energy & Minerals 10.9%
		> Oil Services 5.2%
	5,640,000	FMC Technologies (a)		319,788
		Oil & Gas Wellhead Manufacturer
	3,900,000	Fugro (Netherlands) (b)		298,939
		Oilfield Services
	1,200,000	Atwood Oceanics (a)		120,288
		Offshore Drilling Contractor
	1,675,000	Dresser-Rand Group (a)		65,409
		Largest Manufacturer of Compressors
	1,804,000	Tesco (a)		51,721
		Developing New Well Drilling Technologies
	1,283,100	ShawCor (Canada)		45,944
		Oil & Gas Pipeline Products
	1,988,000	Tetra Technologies (a)		30,953
		U.S. Based Service Company with Life of Field Approach
	706,000	CARBO Ceramics		26,263
		Natural Gas Well Stimulants
	600,000	Rowan		23,676
		Offshore Drilling Contractor
	640,200	SBM Offshore (Netherlands)		20,081
		Builds & Leases Offshore Vessels to Process & Store Crude Oil
	195,000	Exterran Holdings (a)		15,951
		Natural Gas Compressor Rental & Fabrication
	1,580,000	Enerflex Systems (Canada)		14,264
		Natural Gas Compresser Rental & Fabrication
				1,033,277
		> Oil & Gas Producers 4.9%
	2,700,000	Ultra Petroleum (a)		193,050
		Oil & Gas Producer
	3,125,000	XTO Energy		160,500
		Oil & Gas Producer
	2,400,000	Equitable Resources		127,872
		Natural Gas Producer & Utility
	1,800,000	Southwestern Energy (a)		100,296
		Oil & Gas Producer
	1,656,000	Carrizo Oil & Gas (a)(b)		90,666
		Explores for Natural Gas & Crude Oil

Number of Shares			Value (000)
	1,500,000	Range Resources	$	77,040
		Oil & Gas Producer
	4,000,000	Talisman Energy (Canada)		74,533
		Oil & Gas Producer
	4,629,000	Tullow Oil (United Kingdom)		59,726
		Oil & Gas Producer
	1,400,000	Denbury Resources (a)		41,650
		Oil Producer Using Co2 Injection
	15,000,000	Petro Rubiales Energy (Canada) (a)		22,038
		Oil Production & Exploration in Colombia
	1,300,000	Pacific Stratus Energy (Canada) (a)		16,149
		Oil & Gas Exploration in Colombia
	2,750,000	Vaalco Energy (a)		12,787
		Oil & Gas Producer
	100,000	St. Mary Land & Exploration		3,861
		Oil & Gas Producer
				980,168
		> Mining 0.7%
	7,725,000	Uranium One (South Africa) (a)		69,114
		Uranium Mines in South Africa, Kazakhstan, Australia & the U.S.
	2,900,000	Jubilee Mines (Australia)		57,636
		Nickel Mining in Australia
	1,000,000	Ivanhoe Mines (Canada) (a)		10,943
		Copper Mine Project in Mongolia
				137,693
		> Oil Refining, Marketing & Distribution 0.1%
	435,000	Oneok		19,475
		Natural Gas Distribution, Pipeline Processing & Trading
				19,475
Energy & Minerals: Total				2,170,613
Health Care 8.4%
		> Biotechnology & Drug Delivery 2.3%
	4,000,000	BioMarin (a)		141,600
		Biotech Focused on Orphan Diseases
	655,000	Alexion Pharmaceuticals (a)		49,145
		Biotech Focused on Orphan Diseases
	2,550,000	PDL BioPharma (a)		44,676
		Proprietary Monoclonal Antibodies
	3,720,000	Seattle Genetics (a)(b)		42,408
		Antibody-based Therapies for Cancer
	865,000	Amylin (a)		32,005
		Biotech Company Focused on Diabetes & Obesity
	2,550,000	Medarex (a)		26,571
		Humanized Antibodies
	550,000	Myriad Genetics (a)		25,531
		Drugs/Diagnostics Hybrid
	2,660,000	Array Biopharma (a)(b)		22,397
		Drugs for Cancer & Inflammatory Diseases
	2,500,000	Arena Pharmaceuticals (a)		19,575
		Novel Drug Targeting Technology
	1,650,000	Nektar Therapeutics (a)		11,071
		Drug Delivery Technologies
	2,520,000	Decode Genetics (a)		9,274
		Drugs for Heart Attack, Asthma & Vascular Disease

See accompanying notes to financial statements.

26

Number of Shares			Value (000)
		> Biotechnology & Drug Delivery—continued
	1,675,000	Pharmacopeia (a)(b)	$	7,990
		Biotech Company with Broad Early-stage Pipeline
	2,300,000	Neurogen (a)(b)		7,935
		Development-stage Biotech Focused on Neurology
	2,035,000	Lexicon Genetics (a)		6,166
		Drug Discovery
	1,025,000	Nuvelo (a)		1,876
		Development-stage Biotech Focused on Cardiovascular/Cancer
	187,500	Locus Pharmaceuticals, Series A-1, Pfd. (a)(c)		488
	96,644	Locus Pharmaceuticals, Series B-1, Pfd. (a)(c)		251
		High Throughput Rational Drug Design
	1,249,999	Perlegen Sciences (a)(c)		400
		Large Scale Gene Sequencing
	97,000	La Jolla Pharmaceutical (a)		380
		Lupus Treatment
	359,944	MicroDose Technologies (a)(c)		288
		Drug Inhaler Development
				450,027
		> Medical Equipment & Devices 2.1%
	1,648,000	Hologic (a)		113,119
		Diagnostic & Medical Imaging Equipment for Women's Health
	1,330,000	Orthofix International (a)(b)		77,100
		Bone Fixation & Stimulation Devices
	1,000,000	Edwards Lifesciences (a)		45,990
		Heart Valves
	870,000	Vital Signs (b)		44,474
		Anesthesia, Respiratory & Sleep Products
	700,000	Haemonetics (a)		44,114
		Blood & Plasma Collection Equipment
	725,000	Illumina (a)		42,963
		Leading Tools & Service Provider for Genetic Analysis
	435,000	Kinetic Concepts (a)		23,299
		Wound Healing & Tissue Repair
	552,000	Advanced Medical Optics (a)		13,541
		Medical Devices for Eye Care
				404,600
		> Health Care Services 1.6%
	1,245,000	Charles River Laboratories (a)		81,921
		Pharmaceutical Research
	1,650,000	Rhoen-Klinikum (Germany)		51,605
		Health Care Services
	1,300,000	Lincare Holdings (a)		45,708
		Home Health Care Services
	2,250,000	PSS World Medical (a)		44,032
		Medical Supplies
	3,000,000	Eresearch Technology (a)(b)		35,460
		Clinical Research Services
	1,177,000	OPG Groep (Netherlands)		32,519
		Health Care Supplies & Pharmacies
	900,000	Omnicare		20,529
		Pharmacy Services for Nursing Homes

Number of Shares			Value (000)
	600,000	Healthcare Services Group	$	12,708
		Outsourced Services to Long-term Care Industry
				324,482
		> Medical Supplies 1.4%
	1,090,000	Henry Schein (a)		66,926
		Largest Distributor of Healthcare Products
	1,200,000	Owens & Minor		50,916
		Distribution of Medical Supplies
	1,250,000	ICU Medical (a)(b)		45,013
		Intravenous Therapy Products
	1,775,000	QIAGEN (Netherlands) (a)		37,364
		Life Science Company; DNA/RNA Purification
	486,000	Techne (a)		32,100
		Cytokines, Antibodies & other Reagents for Life Science
	700,000	Cooper		26,600
		Contact Lens Manufacturer
	790,000	Meridian Biosciences		23,763
		Niche Diagnostics/Life Science Company
				282,682
		> Pharmaceuticals 1.0%
	1,115,000	Cephalon (a)		80,012
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	1,090,000	MGI Pharma (a)		44,178
		Specialty Pharmaceuticals for Oncology & Acute Care
	1,000,000	Medicis Pharmaceutical		25,970
		Specialty Pharmaceuticals for Dermatology
	3,100,000	United Drug (Ireland)		17,876
		Irish Pharmaceutical Wholesaler & Outsourcer
	4,000,000	QLT (a)(b)		17,680
		Specialty Pharmaceuticals for Ophthalmology & Dermatology
	1,200,000	Collagenex Pharmaceuticals (a)(b)		11,460
		Specialty Pharmaceuticals for Dermatology
	1,780,000	Barrier Therapeutics (a)(b)		7,013
		Specialty Pharmaceuticals for Dermatology
				204,189
Health Care: Total				1,665,980
Other Industries 4.5%
		> Real Estate 2.9%
	2,180,000	Gaylord Entertainment (a)(b)		88,225
		Convention Hotels
	860,000	Federal Realty Investment Trust		70,649
		Shopping Centers
	4,500,000	DiamondRock Hospitality		67,410
		Hotel Owner
	1,398,000	Forest City Enterprises, Class B (b)		62,267
		Commercial & Residential Property Developer
	650,000	SL Green Realty		60,749
		Manhattan Office Buildings
	1,320,000	General Growth Properties		54,358
		Regional Shopping Malls
	635,000	Macerich Company		45,123
		Regional Shopping Malls
	850,000	Digital Realty Trust		32,615
		Technology-focused Office Buildings

See accompanying notes to financial statements.

27

Columbia Acorn Fund

Statement of Investments, continued

Number of Shares or Principal Amount (000)			Value (000)
		> Real Estate—continued
	1,720,000	Kite Realty Group (b)	$	26,264
		Community Shopping Centers
	900,000	American Campus Communities		24,165
		Student Housing
	628,000	Parkway Properties		23,223
		Office Buildings
	1,000,000	BioMed Realty Trust		23,170
		Life Science-focused Office Buildings
	8,200	Kenedix (Japan)		13,194
		Real Estate Investment Management
	37,407	Security Capital European Realty (Luxembourg) (a)(c)(d)		—
		Self Storage Properties
				591,412
		> Transportation 1.3%
	3,000,000	JB Hunt Transport Services		82,650
		Truck & Intermodal Carrier
	826,200	Grupo Aeroportuario del Surest (Mexico)		50,580
		Cancun & Cozumel Airport Operator
	3,000,000	Heartland Express		42,540
		Regional Trucker
	38,000,000	Jiangsu Expressway (China)		41,007
		Chinese Toll Road Operator
	7,820,000	China Shipping Development (China)		20,393
		China's Dominant Shipper for Oil & Coal
	956,000	Rush Enterprises (a)		17,380
		Truck Distribution
				254,550
		> Regulated Utilities 0.3%
	1,800,000	Northeast Utilities		56,358
		Regulated Electric Utility
				56,358
Other Industries: Total				902,320
Total Equities: 95.9% (Cost: $12,297,767)				19,099,687
Short-Term Obligations 4.2%
$	100,000	Hewlett Packard (e) 4.23% Due 1/07/08 – 1/08/08		99,924
	80,000	Nestle Capital (e) 4.15% Due 1/11/08 – 1/24/08		79,862
	50,000	Emerson Electric (e) 4.20% Due 1/02/08		49,994
		General Electric Capital:
	50,000	4.10% Due 1/03/08		49,989
	50,000	4.20% Due 1/17/08		49,907
		Hershey Foods: (e)
	50,000	4.48% Due 1/07/08		49,963
	20,000	4.23% Due 1/08/08		19,984

Principal Amount (000)			Value (000)
		Toyota Motor Credit:
$	50,000	4.18% Due 1/09/08	$	49,954
	25,000	4.15% Due 1/04/08		24,991
	25,000	4.20% Due 1/18/08		24,950
		United Parcel Service: (e)
	50,000	4.36% Due 1/10/08		49,945
	50,000	4.365% Due 1/11/08		49,939
	50,000	Caterpillar Finance 4.22% Due 1/14/08		49,924
	41,635	Genentech (e) 4.26% Due 1/18/08		41,551
	41,100	IBM International Group (e) 4.39% Due 1/11/08		41,050
	19,925	IBM Corporation (e) 4.21% Due 1/02/08		19,923
	19,000	Nestle Finance 4.40% Due 1/11/08		18,977
	10,000	Walgreen Co. (e) 4.20% Due 1/02/08		9,999
	57,143	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by U.S. Government Agency Obligations with various maturities to 7/18/16, market value $58,287 (repurchase proceeds $57,153)		57,143
(Amortized Cost: $837,969)				837,969
Total Investments: 100.1% (Cost: $13,135,736)(f)(g)				19,937,656
Cash and Other Assets Less Liabilities: (0.1)%				(16,310	)
Total Net Assets: 100%			$	19,921,346

See accompanying notes to financial statements.

28

> Notes to Statement of Investments (dollar values in thousands)

(a)  Non-income producing security.

(b)  An affiliate may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in these affiliated companies during the twelve months ended December 31, 2007, are as follows:

Affiliates	Balance of Shares Held 12/31/06		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/07		Value		Dividend
Actuate		6,000,000		-		1,000,000		5,000,000	$	38,850	$	-
Administaff		1,670,000		355,000		-		2,025,000		57,267		839
AFC Enterprises		1,600,000		200,000		-		1,800,000		20,376		-
Agile Software*		3,500,000		-		3,500,000		-		-		-
AmeriCredit		6,500,000		735,000		-		7,235,000		92,536		-
Anchor Bancorp Wisconsin*		1,178,000		-		404,000		774,000		18,204		680
AnswerThink		4,600,000		-		-		4,600,000		22,264		-
Array Biopharma		1,780,000		880,000		-		2,660,000		22,397		-
Bally Technologies		3,500,000		-		350,000		3,150,000		156,618		-
Barrier Therapeutics		1,321,000		459,000		-		1,780,000		7,013		-
Belden CDT		1,945,000		335,000		-		2,280,000		101,460		430
BOK Financial		2,605,000		895,000		-		3,500,000		180,950		2,322
CAI International		-		1,500,000		-		1,500,000		15,780		-
Carrizo Oil & Gas		-		1,656,000		-		1,656,000		90,666		-
Chattem		1,010,000		-		-		1,010,000		76,296		-
Chico's FAS*		7,080,000		2,050,000		1,530,000		7,600,000		68,628		-
Christopher & Banks		3,743,000		-		943,000		2,800,000		32,060		842
Clarcor		3,500,000		-		-		3,500,000		132,895		1,041
Cogent Communications		1,000,000		1,836,000		-		2,836,000		67,241		-
Collagenex Pharmaceuticals		830,000		370,000		-		1,200,000		11,460		-
Concur Technologies*		2,131,000		-		731,000		1,400,000		50,694		-
Cytokinetics*		2,000,000		-		2,000,000		-		-		-
Dobson Communications*		8,000,000		-		8,000,000		-		-		-
Donaldson		3,600,000		600,000		-		4,200,000		194,796		1,506
Drew Industries		1,228,000		150,000		-		1,378,000		37,757		-
Enerflex Systems*		2,280,000		8,100		708,100		1,580,000		14,264		1,316
Epicor		-		3,500,000		-		3,500,000		41,230		-
Eresearch Technology		2,300,000		700,000		-		3,000,000		35,460		-
ESCO Technologies		2,200,000		-		-		2,200,000		87,868		-
Excel Technology		625,000		110,000		-		735,000		19,918		-
FARO Technologies		-		1,044,000		-		1,044,000		28,376		-
First Mutual Bancshares		400,000		-		-		400,000		10,572		144
Fleetwood Enterprises*		4,690,000		1,000,000		3,925,000		1,765,000		10,555		-
Forest City Enterprises, Class B		1,398,000		-		-		1,398,000		62,267		419
Forward Air		1,900,000		-		-		1,900,000		59,223		532
Fugro		2,928,301		971,699		-		3,900,000		298,939		3,860
Gaiam		1,200,000		-		-		1,200,000		35,616		-
Gaylord Entertainment		1,760,000		420,000		-		2,180,000		88,225		-
Genlyte Group*		1,963,000		637,000		1,650,000		950,000		90,440		-
Gibraltar Industries		2,860,000		-		-		2,860,000		44,101		715
Glacier Bancorp		4,080,000		166,000		-		4,246,000		79,570		2,021
Helen of Troy		1,800,000		100,000		-		1,900,000		32,566		-
Herman Miller		2,068,000		1,932,000		-		4,000,000		129,560		1,186
Highland Hospitality*		5,850,000		-		5,850,000		-		-		1,346
HNI*		2,550,000		-		550,000		2,000,000		70,120		1,758
ICU Medical		1,083,000		167,000		-		1,250,000		45,013		-
iGate		5,000,000		-		-		5,000,000		42,350		-
II-VI		2,025,000		375,000		-		2,400,000		73,320		-
Interline Brands		-		1,700,000		-		1,700,000		37,247		-
Indus International (merged into Vista Equity)*		5,600,000		-		5,600,000		-		-		-
ITT Educational Services		2,250,000		-		250,000		2,000,000		170,540		-
IXYS		1,905,000		-		-		1,905,000		15,278		-
JDA Software*		1,490,000		-		1,490,000		-		-		-
Kaydon		1,100,000		596,000		-		1,696,000		92,500		693
Kenexa		828,000		1,597,000		-		2,425,000		47,094		-
Kite Realty Group		1,720,000		-		-		1,720,000		26,264		1,359
Knoll		1,809,000		1,591,000		-		3,400,000		55,862		1,180

See accompanying notes to financial statements.

29

Columbia Acorn Fund

Statement of Investments, continued

> Notes to Statement of Investments (dollar values in thousands)

Affiliates	Balance of Shares Held 12/31/06		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/07		Value		Dividend
Kronos (merged into Helman & Friedman)*		2,750,000		-		2,750,000		-	$	-	$	-
LCA-Vision*		1,125,000		-		1,125,000		-		-		608
Littelfuse		1,135,000		285,000		-		1,420,000		46,803		-
Marchex		-		1,700,000		-		1,700,000		18,462		59
Marlin Business Services		685,000		415,000		-		1,100,000		13,266		-
McGrath Rentcorp		1,212,000		488,000		-		1,700,000		43,775		938
Meadowbrook Insurance Group		-		2,000,000		-		2,000,000		18,820		-
Mine Safety Appliances		1,900,000		-		86,000		1,814,000		94,092		1,558
Mobile Mini		1,650,000		100,000		-		1,750,000		32,445		-
Navigant Consulting		1,900,000		600,000		-		2,500,000		34,175		-
Neurogen		655,000		1,645,000		-		2,300,000		7,935		-
Orthofix International		942,500		387,500		-		1,330,000		77,100		-
Oxford Industries		919,000		150,000		-		1,069,000		27,548		743
Pharmacopeia		-		1,675,000		-		1,675,000		7,990		-
Pinnacle Entertainment		3,200,000		850,000		-		4,050,000		95,418		-
Pool		2,500,000		390,000		-		2,890,000		57,309		1,329
Princeton Review		2,550,000		-		-		2,550,000		21,242		-
ProQuest*		2,000,000		-		2,000,000		-		-		-
QLT		2,500,000		1,500,000		-		4,000,000		17,680		-
Quality Systems		-		1,510,000		-		1,510,000		46,040		348
Radiant Systems		2,500,000		-		-		2,500,000		43,075		-
Red Robin Gourmet Burgers		1,000,000		-		-		1,000,000		31,990		-
Saga Communications		1,400,000		-		-		1,400,000		8,246		-
Salem Communications		1,541,000		-		-		1,541,000		10,155		647
Sanmina-SCI		10,000,000		19,500,000		-		29,500,000		53,690		-
Seachange International*		1,875,000		-		1,875,000		-		-		-
Seattle Genetics		2,300,000		1,420,000		-		3,720,000		42,408		-
Shuffle Master		2,430,000		-		-		2,430,000		29,136		-
SkillSoft		9,500,000		-		-		9,500,000		90,820		-
Spanish Broadcasting System		2,400,000		-		-		2,400,000		4,440		-
Spartech*		2,700,000		-		2,700,000		-		-		1,008
Supertex		690,000		340,000		130,000		900,000		28,161		-
Switch & Data Facilities		-		2,000,000		-		2,000,000		32,040		-
Time Warner Telecom		4,500,000		3,500,000		-		8,000,000		162,320		-
TriCo Bancshares		-		900,000		-		900,000		17,370		219
TrueBlue		-		2,300,000		-		2,300,000		33,304		-
Tumbleweed Communications*		3,500,000		-		3,500,000		-		-		-
United America Indemnity*		1,550,000		-		1,550,000		-		-		-
Universal Technical Institute		1,500,000		-		-		1,500,000		25,500		-
Vaalco Energy*		3,200,000		-		450,000		2,750,000		12,787		-
Vail Resorts		2,390,000		-		-		2,390,000		128,606		-
Viad		-		1,453,000		-		1,453,000		45,886		70
Vital Signs		870,000		-		-		870,000		44,474		339
Voyager Learning		-		2,000,000		-		2,000,000		14,300		-
Watsco		2,375,000		-		-		2,375,000		87,305		3,111
West Bancorporation		949,000		363,000		-		1,312,000		17,108		740
West Coast Bancorp		1,320,000		117,000		-		1,437,000		26,584		669
Witness Systems*		2,500,000		-		2,500,000		-		-		-
World Acceptance		1,500,000		175,000		-		1,675,000		45,191		-
TOTAL OF AFFILIATED TRANSACTIONS		230,096,801		76,399,299		57,147,100		249,349,000	$	5,035,542	$	36,575

*  At December 31, 2007, the Fund owned less than five percent or more of the company's outstanding voting shares.

  The aggregate cost and value of these companies at December 31, 2007, was $3,677,369 and $5,035,542 respectively. Investments in affiliate companies represented 25.3% of the Fund's total net assets at December 31, 2007.

See accompanying notes to financial statements.

30

> Notes to Statement of Investments (dollar values in thousands)

(c)  Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued in good faith by the board of trustees. At December 31, 2007, these securities amounted to $1,427 which represented 0.01% of total net assets.

  Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Perlegen Sciences	3/30/01		1,249,999	$	4,500	$	400
Locus Pharmaceuticals, Series A-1 Pfd.	9/5/01		187,500		7,500		488
MicroDose Technologies	11/24/00		359,944		2,005		288
Locus Pharmaceuticals, Series B-1 Pfd.	2/8/07		96,644		280		251
Security Capital European Realty	8/20/98-11/12/99		37,407		205		-
				$	14,490	$	1,427

(d)  Security has no value.

(e)  Security exempt from registration under Section 4(2) of the Securities Act of 1933. These securities may only be resold in exempt transactions to qualified buyers. Private resales of these securities to qualified institutional buyers are also exempt from registration pursuant to Rule 144A under the Securities Act of 1933. At December 31, 2007, these securities had an aggregate value of $512,134, which represented 2.6% of net assets.

(f)  At December 31, 2007, for federal income tax purposes cost of investments was $13,141,866 and net unrealized appreciation was $6,795,790 consisting of gross unrealized appreciation of $7,838,307 and gross unrealized depreciation of $1,042,517.

(g)  On December 31, 2007, the market value of foreign securities represented 11.63% of total net assets. The Fund's foreign portfolio was diversified as follows:

	Value		Percent
Netherlands	$	467,017		2.34	%
Canada		210,890		1.06
Japan		202,524		1.02
France		189,368		0.95
Germany		111,674		0.56
China		110,189		0.55
United Kingdom		103,427		0.52
Sweden		99,911		0.50
India		96,864		0.49
Australia		96,618		0.48
Hong Kong		92,641		0.47
South Africa		69,114		0.35
Denmark		59,818		0.30
	Value		Percent
Mexico	$	50,580		0.25	%
Israel		48,940		0.25
Greece		46,898		0.24
Ireland		46,237		0.23
Switzerland		43,234		0.22
Singapore		36,564		0.18
Chile		34,466		0.17
Austria		26,921		0.14
Taiwan		23,983		0.12
Brazil		22,773		0.11
Spain		14,875		0.07
Italy		11,056		0.06
Luxembourg		-		-
Total Foreign Portfolio	$	2,316,582		11.63	%

See accompanying notes to financial statements.

31

Columbia Acorn International

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	09/30/07		12/31/07
Additions
Europe
> France
Neopost		160,000		280,000
Sperian Protection		190,000		225,000
> Netherlands
SBM Offshore		450,000		475,300
Vopak		0		450,000
> Germany
CTS Eventim		750,000		850,000
Hamburger Hafen und Logistik		0		275,000
MPC Muechmeyer Petersen Capital		330,000		400,000
Rational		140,000		155,000
Vossloh		250,000		300,000
> United Kingdom
Detica		2,375,000		3,000,000
Informa Group		2,400,000		3,000,000
Intertek Testing		1,000,000		1,600,000
> Sweden
Securitas Systems		8,900,000		10,400,000
> Ireland
Grafton Group		1,040,000		1,200,000
Kingspan Group		665,000		845,000
United Drug		8,416,000		8,840,000
> Italy
Cobra Automotive		0		580,000
> Austria
Wienerberger		400,000		549,332
Zumtobel		1,052,000		1,200,000
Asia
> Japan
Casio Computer		0		1,950,000
Hirose Electric		72,000		175,000
OSG		0		1,800,000
Point		200,000		273,000
SYSMEX		440,000		536,000
Topcon		1,300,000		1,700,000
Unicharm PetCare		329,300		373,000
Union Tool		500,000		608,000
Yusen Air & Sea Service		1,344,000		1,580,000
> China
Fu Ji Food & Catering Services		7,500,000		9,300,000
Lenovo Group		48,430,000		55,730,000
Sinotrans		0		30,500,000
VisionChina Media		0		556,500
Xinyu Hengdeli		30,890,000		34,000,000

	Number of Shares
	09/30/07		12/31/07
Asia—continued
> South Korea
JVM		0		116,500
Mirae Asset Securities		0		57,700
Woongjin Coway		977,000		1,192,000
> Hong Kong
Hong Kong Aircraft Engineering		0		700,000
Lifestyle International		10,000,000		12,750,000
> Singapore
ComfortDelGro		17,000,000		20,000,000
OLAM		4,000,000		10,000,000
> Taiwan
Everlight Electronics		3,604,723		7,004,722
Formosa International Hotels		795,826		1,995,826
GeoVision		0		1,500,000
Other Countries
> United States
Decode Genetics		0		1,135,000
Tesco		379,239		450,000
> Australia
Australian Stock Exchange		750,000		850,000
Sino Gold		5,480,000		5,843,650
> South Africa
Mr. Price		4,460,000		7,600,000
> Canada
CCL		0		127,100
> New Zealand
Sky City Entertainment		5,773,789		5,932,812
Latin America
> Brazil
BM&F		0		1,010,100
Bovespa		0		2,000,000
Localiza Rent A Car		2,000,000		3,000,000
> Mexico
Financiera Independencia		0		6,000,000
Megacable		0		4,000,000

See accompanying notes to financial statements.

32

	Number of Shares
	09/30/07		12/31/07
Sales
Europe
> France
Carbone Lorraine		600,000		534,000
> Netherlands
USG People		705,000		410,000
> Germany
Deutsche Boerse		250,000		125,000
> Switzerland
Nobel Biocare Holding		165,000		110,000
Synthes		360,000		300,000
> United Kingdom
BBA Group		3,007,000		0
Tullow Oil		3,255,691		1,798,000
> Russia
RosBusinessConsulting		486,000		473,671
> Poland
Central European Distribution		1,125,500		830,000
Asia
> Japan
Ito En		718,000		500,000
Nagaileben		123,900		64,000
USS		430,000		293,000
> China
China Shipping Development		23,547,000		21,318,000
> South Korea
Taewoong		444,000		337,000
> Hong Kong
Hong Kong Exchanges and Clearing		4,000,000		2,500,000
> India
Housing Development Finance		1,300,000		1,000,000
> Taiwan
Advantech		7,306,757		4,145,000

	Number of Shares
	09/30/07		12/31/07
Other Countries
> United States
Atwood Oceanics		865,000		725,000
> Canada
Talisman Energy		865,000		0
Latin America
> Brazil
Natura Cosmeticos		2,500,000		1,500,000
> Mexico
Consorcio ARA		18,000,000		0

See accompanying notes to financial statements.

33

Columbia Acorn International

Statement of Investments, December 31, 2007

Number of Shares			Value (000)
				Equities: 95.2%
Europe 49.4%
		> France 8.6%
	3,000,000	SES Global	$	78,666
		Satellite Broadcasting Services
	500,000	Iliad		53,417
		Alternative Internet & Telecoms Provider
	375,000	Norbert Dentressangle		39,157
		Transport
	380,000	Rubis		37,077
		Tank Storage & LPG Supplier
	534,000	Carbone Lorraine		36,796
		Advanced Industrial Materials
	280,000	Neopost		28,752
		Postage Meter Machines
	206,000	Pierre & Vacances		28,460
		Vacation Apartment Lets
	656,700	Trigano		28,362
		Leisure Vehicles & Camping Equipment
	240,000	Eurofins Scientific		27,812
		Food Screening & Testing
	225,000	Sperian Protection		25,590
		Safety Equipment
	700,000	Legrand		23,776
		Electrical Components
	350,000	April Group		23,495
		Insurance Policy Construction
	251,000	Imerys		20,554
		Industrial Minerals Producer
	410,000	Meetic (a)		17,905
		Dating Services
	100,000	Ciments Francais		17,121
		Leading French & Emerging Markets Cement Producer
	1,100,000	Hi-Media		9,683
		Leading Online Advertiser in Europe
				496,623
		> Netherlands 8.0%
	1,406,155	Fugro		107,783
		Oilfield Services
	686,800	Smit Internationale		69,933
		Harbor & Offshore Towage & Marine Services
	1,385,000	Unit 4 Agresso (b)		39,345
		Business & Security Software
	1,947,042	Aalberts Industries		38,377
		Flow Control & Heat Treatment
	1,437,000	Imtech		35,317
		Engineering & Technical Services
	1,096,000	Koninklijke TenCate		33,878
		Advanced Textiles & Industrial Fabrics
	489,000	Boskalis Westminster		29,706
		Dredging & Maritime Contractor
	450,000	Vopak		25,454
		World's Largerst Operator of Petroleum & Chemical Storage Terminals
	833,000	OPG Groep		23,015
		Health Care Supplies & Pharmacies
	1,525,000	Wavin		20,172
		Largest European Plastic Pipe Systems Company

Number of Shares			Value (000)
	800,000	QIAGEN (a)	$	17,181
		Life Science Company; DNA/RNA Purification
	475,300	SBM Offshore		14,909
		Builds & Leases Offshore Vessels to Process & Store Crude Oil
	410,000	USG People		10,991
		Temporary Staffing Services
				466,061
		> Germany 6.7%
	1,800,000	Rhoen-Klinikum		56,296
		Health Care Services
	500,000	Wincor Nixdorf		47,119
		Retail POS Systems & ATM Machines
	310,987	Elringklinger		38,647
		Automobile Components
	400,000	MPC Muechmeyer Petersen Capital		35,507
		Alternative Asset Manager
	300,000	Vossloh		35,080
		Rail Infrastructure & Diesel Locomotives
	850,000	CTS Eventim		32,670
		Event Ticket Sales
	155,000	Rational		31,711
		Commercial Oven Manufacturer
	125,000	Deutsche Boerse		24,673
		Trading, Clearing, Settlement Services for Financial Markets
	275,000	Hamburger Hafen und Logistik (a)		24,526
		Terminal Operator at the Hamburg Port
	525,000	GFK		21,026
		Market Research Services
	918,000	Takkt		15,955
		Mail Order Retailer of Office & Warehouse Durables
	7,500	Porsche		15,114
		Specialty Automobile Manufacturer
	354,500	Deutsche Beteiligungs		11,088
		Private Equity Investment Management
				389,412
		> Switzerland 5.4%
	600,000	Kuehne & Nagel		57,203
		Freight Forwarding/Logistics
	140,000	Burckhardt Compression		45,243
		Gas Compression Pumps
	24,000	Sika		45,114
		Chemicals for Construction & Industrial Applications
	300,000	Synthes		37,082
		Products for Orthopedic Surgery
	250,000	Geberit		34,083
		Plumbing Supplies
	110,000	Nobel Biocare Holding		29,099
		Dental Implants & Ceramic Crowns
	450,000	Schindler		28,766
		Elevator Manufacturer & Service Provider
	25,000	Givaudan		24,020
		Fragrances & Flavors
	400,000	Logitech International (a)		14,523
		Branded Peripheral Computer Devices
				315,133

See accompanying notes to financial statements.

34

Number of Shares			Value (000)
		> United Kingdom 5.4%
	1,970,714	Expro International Group	$	40,197
		Offshore Oilfield Services
	2,500,000	Northgate		38,009
		Light Commercial Vehicle Rental Specialist
	3,000,000	Smith & Nephew		34,491
		Medical Equipment & Supplies
	1,600,000	Intertek Testing		31,370
		Testing, Inspection, Certification Services
	7,000,000	Taylor Nelson Sofres		28,684
		Market Research
	3,000,000	Informa Group		27,441
		Global Publisher & Event Organizer
	4,230,000	RPS Group		26,806
		Environmental Consulting & Planning
	640,000	Randgold Resources		23,763
		Gold Mining in Western Africa
	1,798,000	Tullow Oil		23,199
		Oil & Gas Producer
	1,002,000	Rotork		19,177
		Valve Actuators for Oil & Water Pipelines
	3,000,000	Detica		13,082
		UK IT Services Company
	650,000	Keller Group		8,504
		International Ground Engineering Specialist
				314,723
		> Sweden 2.9%
	3,960,000	Hexagon		81,661
		Measurement Equipment & Polymers
	10,400,000	Securitas Systems		36,691
		Commercial Security Installation & Service
	3,135,000	SWECO		31,359
		Engineering Consultants
	2,265,000	Nobia		20,083
		Kitchen Cabinet Manufacturing & Distribution
				169,794
		> Ireland 2.3%
	8,840,000	United Drug		50,975
		Irish Pharmaceutical Wholesaler & Outsourcer
	1,800,000	IAWS Group		39,844
		Baked Goods
	600,000	Paddy Power		19,739
		Irish Betting Services
	845,000	Kingspan Group		12,735
		Building Insulation & Environmental Containers
	1,200,000	Grafton Group (a)		9,431
		Builders Materials Wholesaling & Do-it-yourself Retailing
				132,724
		> Italy 1.9%
	9,100,000	CIR		33,430
		Italian Holding Company
	12,531,048	Ducati Motor (a)		25,608
		Motorcycles & Related Merchandise
	3,750,000	Amplifon		18,924
		Hearing Aid Retailer
	1,243,000	GranitiFiandre		15,809
		Innovative Stoneware

Number of Shares			Value (000)
	375,000	Sabaf	$	12,117
		Supplier to White Goods Original Equipment Manufacturer
	580,000	Cobra Automotive (a)		5,379
		Electronic Car Theft Protection
				111,267
		> Greece 1.3%
	3,790,000	Intralot		74,681
		Lottery & Gaming Systems & Services
				74,681
		> Austria 1.3%
	1,200,000	Zumtobel		43,074
		Lighting Systems
	549,332	Wienerberger		30,345
		Bricks & Clay Roofing Tiles
				73,419
		> Spain 1.2%
	400,000	Red Electrica de Espana		25,138
		Spanish Power Grid
	600,000	Sogecable (a)		23,906
		Spain's Main Pay-TV
	1,050,000	Prisa		19,523
		Leading Spanish-speaking Publisher
				68,567
		> Finland 1.0%
	1,756,000	Poyry		44,107
		Engineering Consultants
	354,000	Stockmann		15,247
		Department Stores in Finland, Baltics & Russia
				59,354
		> Russia 0.9%
	775,000	Novolipetsk Steel (a)		31,698
		Vertically Integrated Steel Producer
	473,671	RosBusinessConsulting		19,610
		Financial Information, Media & IT Services in Russia
				51,308
		> Poland 0.8%
	830,000	Central European Distribution (a)		48,206
		Vodka Production & Alcohol Distribution
				48,206
		> Czech Republic 0.8%
	183,000	Komercni Banka		44,034
		Leading Czech Universal Bank
				44,034
		> Denmark 0.5%
	265,000	Novozymes		29,909
		Industrial Enzymes
				29,909
		> Norway 0.4%
	2,774,800	Kongsberg Automotive (b)		20,388
		Automotive Seating & Component Supplier
				20,388
Europe: Total				2,865,603

See accompanying notes to financial statements.

35

Columbia Acorn International

Statement of Investments, continued

Number of Shares			Value (000)
Asia 29.4%
		> Japan 13.1%
	730,000	Ibiden	$	50,422
		Electronic Parts & Ceramics
	6,000,000	Kansai Paint		43,521
		Paint Producer in Japan, India, China & Southeast Asia
	1,700,000	Ushio		37,312
		Industrial Light Sources
	43,500	Jupiter Telecommunications (a)		36,799
		Largest Cable Service Provider in Japan
	1,580,000	Yusen Air & Sea Service		35,783
		Airfreight Logistics
	1,080,000	Hoya		34,468
		Opto-electrical Components & Eyeglass Lenses
	4,000,000	Park24		30,804
		Parking Lot Operator
	18,000	Kenedix		28,963
		Real Estate Investment Management
	816,200	Kintetsu World Express		28,244
		Airfreight Logistics
	885,000	Aeon Mall		23,230
		Suburban Shopping Mall Developer, Owner & Operator
	536,000	SYSMEX		22,737
		In Vitro Diagnostics (IVD) Equipment & Reagent Manufacturer
	1,950,000	Casio Computer		22,695
		Micro-consumer Electronic Goods
	10,000	Risa Partners		21,879
		NPL & Real Estate Related Investment
	1,150,000	FCC		20,462
		Auto/Motorcycle Clutches
	175,000	Hirose Electric		20,275
		Electrical Connectors
	608,000	Union Tool		20,110
		Precision Drill Bit Manufacturer
	1,600,000	Cosel		19,862
		Industrial Standard Switching Power Supply System
	1,800,000	OSG		19,690
		Consumable Cutting Tools
	373,000	Unicharm PetCare		19,328
		Pet Food & Pet Toiletries
	6,000,000	Kansai Urban Banking		18,881
		Regional Bank
	145,000	Nakanishi		18,742
		Dental Tools & Machinery
	293,000	USS		18,178
		Used Car Auctioneer
	700,000	As One		16,447
		Scientific Supplies Distributor
	1,700,000	Topcon		15,998
		Positioning & Medical Instrument
	965,000	T. Hasegawa		15,141
		Industrial Flavors & Fragrances
	273,000	Point		13,870
		Apparel Specialty Retailer
	2,300,000	Bank of Fukuoka		13,718
		Regional Bank

Number of Shares			Value (000)
	2,400	Osaka Securities Exchange	$	11,176
		Osaka Securities Exchange
	380,000	Takata		11,035
		Safety Related Auto Parts
	500,000	Ito En		9,520
	215,400	Ito En, Pfd.		3,072
		Bottled Tea & Other Beverages
	643,000	Ain Pharmaciez (b)		9,329
		Dispensing Pharmacy/Drugstore Operator
	506,000	Aeon Delight		9,247
		Facility Maintenance & Management
	1,230,000	Kamigumi		8,888
		Port Cargo Handling & Logistics
	4,000	Wacom		8,338
		Computer Graphic Illustration Devices
	14,000	FullCast (b)		8,192
		Employment Outsourcing
	1,650	Japan Pure Chemical		6,166
		Precious Metal Plating Chemicals for Electronics
	2,900	Message		5,646
		Nursing Care Facility Operator
	64,000	Nagaileben		1,114
		Medical/Health Care Related Clothes
				759,282
		> China 5.2%
	21,318,000	China Shipping Development		55,594
		China's Dominant Shipper for Oil & Coal
	55,730,000	Lenovo Group		49,275
		Third Largest PC Vendor Globally
	29,648,000	China Green		31,534
		Agricultural Grower & Processor in China
	26,508,000	Jiangsu Expressway		28,606
		Chinese Toll Road Operator
	20,910,000	Travelsky Technology		22,034
		Online Air Travel Bookings in China
	400,000	Sohu.com (a)		21,808
		Advertising on Chinese Internet Portal
	25,000,000	Hopewell Highway Infrastructure		21,425
		Guangdong Tollroad Leading to Hong Kong & Macau
	9,300,000	Fu Ji Food & Catering Services		21,330
		Food Catering Service Provider in China
	34,000,000	Xinyu Hengdeli		19,070
		A High-end Watch Retailer in China
	21,750,000	TPV Technology		15,716
		Original Design Manufacturer for LCD Monitor & Flat TV
	30,500,000	Sinotrans		13,325
		Largest Integrated Logistics Player in China
	556,500	VisionChina Media (a)		4,730
		Advertising on Digital Screens in China's Mass Transit System
				304,447
		> South Korea 2.8%
	154,301	MegaStudy		43,685
		Online Education Service Provider
	1,192,000	Woongjin Coway		38,403
		South Korean Household Appliance Rental Service Provider

See accompanying notes to financial statements.

36

Number of Shares			Value (000)
		> South Korea—continued
	337,000	Taewoong	$	31,631
		A Player in the Niche Customized Forging Market
	915,000	Sung Kwang Bend		26,261
		A Large Customized Industrial Pipe Fitting Manufacturer
	57,700	Mirae Asset Securities		10,402
		Korean Largest Diversified Financial Company
	116,500	JVM (a)		7,008
		Automatic Tablet Dispensing & Packaging Systems
	262,000	YBM Sisa.com		4,159
		Online Language Educator & Tester
				161,549
		> Hong Kong 2.3%
	2,500,000	Hong Kong Exchanges and Clearing		70,182
		Hong Kong Equity & Derivatives Market Operator
	12,750,000	Lifestyle International		34,312
		Mid to High-end Department Store Operator in Hong Kong & China
	700,000	Hong Kong Aircraft Engineering		18,883
		Aircraft Maintenance, Repair, Overhaul Operator
	46,000,000	Global Digital Creations (a)		9,971
		Digital Cinema Solution Provider/ Network Operator
				133,348
		> India 2.3%
	1,000,000	Housing Development Finance		71,751
		Indian Mortgage Lender
	4,450,000	United Phosphorus		39,419
		Off-patent Crop Protection Chemicals
	700,000	Asian Paints		19,438
		India's Largest Paint Company
	40,705	JSW Steel		1,354
		Flat Steel Producer in India
				131,962
		> Singapore 1.9%
	7,000,000	Singapore Exchange		63,987
		Singapore Equity & Derivatives Market Operator
	20,000,000	ComfortDelGro		25,164
		Taxi & Mass Transit Service
	10,000,000	OLAM		19,658
		Agriculture Supply Chain Manager
				108,809
		> Taiwan 1.4%
	7,004,722	Everlight Electronics		25,486
		Led Packager
	1,995,826	Formosa International Hotels		17,906
		Hotel, Food & Beverage Operation & Hospitality Management Services
	7,501,588	Wah Lee Industrial		14,273
		Distributor of Chemicals, Materials & Equipment
	1,500,000	GeoVision		13,729
		Taiwan PC-based Video Surveillance Player
	4,145,000	Advantech		9,400
		Embedded Computers
				80,794

Number of Shares			Value (000)
		> Indonesia 0.4%
	15,000,000	Perusahaan Gas Negara	$	24,288
		Gas Pipeline Operator
				24,288
Asia: Total				1,704,479
Other Countries 11.0%
		> Australia 3.2%
	850,000	Australian Stock Exchange		44,944
		Australian Equity & Derivatives Market Operator
	2,000,000	Jubilee Mines		39,750
		Nickel Mining in Australia
	3,000,000	Billabong International		38,982
		Action Sports Apparel Brand Manager
	5,843,650	Sino Gold (a)		35,364
		Gold Mining in The People's Republic of China
	475,000	Perpetual Trustees		27,661
		Mutual Fund Management
				186,701
		> United States 3.0%
	725,000	Atwood Oceanics (a)		72,674
		Offshore Drilling Contractor
	758,000	FMC Technologies (a)		42,979
		Oil & Gas Wellhead Manufacturer
	565,000	Dresser-Rand Group (a)		22,063
		Largest Manufacturer of Compressors
	600,000	BioMarin (a)		21,240
		Biotech Focused on Orphan Diseases
	450,000	Tesco (a)		12,901
		Developing New Well Drilling Technologies
	1,135,000	Decode Genetics (a)		4,177
		Drugs for Heart Attack, Asthma & Vascular Disease
				176,034
		> South Africa 2.6%
	1,440,000	Impala Platinum Holdings		49,678
		Platinum Group Metals Mining & Refining
	4,299,000	Uranium On (a)		38,462
		Uranium Mines in South Africa, Kazakhstan, Australia & the U.S.
	1,560,000	Naspers		36,721
		Media & Education in Africa & other Emerging Markets
	7,600,000	Mr. Price		24,444
		South African Retailer of Apparel, Household Goods & Sporting Goods
				149,305
		> Canada 1.8%
	1,860,000	ShawCor		66,602
		Oil & Gas Pipeline Products
	1,333,000	RONA (a)		23,028
		Leading Canadian Do-it-yourself Retailer
	850,000	Ivanhoe Mines (a)		9,301
		Copper Mine Project in Mongolia

See accompanying notes to financial statements.

37

Columbia Acorn International

Statement of Investments, continued

Number of Shares			Value (000)
		> Canada—continued
	127,100	CCL	$	4,972
		Leading Global Label Manufacturer
				103,903
		> New Zealand 0.4%
	5,932,812	Sky City Entertainment		21,002
		Casino/Entertainment Complex
				21,002
Other Countries: Total				636,945
Latin America 5.4%
		> Brazil 3.5%
	4,300,000	Suzano		69,650
		Brazilian Pulp & Paper Producer
	2,000,000	Bovespa (a)		38,539
		Brazil Equity & Derivative Exchange
	3,000,000	Localiza Rent A Car		31,545
		Car Rental
	800,000	Porto Seguro		29,365
		Auto & Life Insurance
	1,500,000	Natura Cosmeticos		14,195
		Direct Retailer of Cosmetics
	1,010,100	BM&F (a)		14,187
		Brazilian Derivatives Exchange
	520,800	Redecard		8,338
		Credit/Debit Card Acquirer/Processor
				205,819
		> Mexico 1.4%
	500,000	Grupo Aeroportuario del Surest		30,610
		Cancun & Cozumel Airport Operator
	7,000,000	Urbi Desarrollos Urbanos (a)		24,179
		Affordable Housing Builder
	4,000,000	Megacable (a)		13,582
		Mexican Cable & Internet Operator
	6,000,000	Financiera Independencia (a)		10,302
		Mexican Micro-finance Lender
				78,673
		> Chile 0.5%
	160,000	Sociedad Quimica y Minera de Chile		28,280
		Producer of Specialty Fertilizers, Lithium & Iodine
				28,280
Latin America: Total				312,772
Total Equities: 95.2% (Cost: $3,666,829)				5,519,799

Principal Amount (000)			Value (000)
Short-Term Obligations 5.4%
$	30,400	United Parcel Service (c) 4.22% Due 1/16/08	$	30,346
	30,300	IBM International Group (c) 4.39% Due 1/02/08		30,296
	29,000	Emerson Electric (c) 4.20% Due 1/02/08		28,997
	29,000	General Electric Capital 4.15% Due 1/04/08		28,990
	28,600	Toyota Motor Credit 4.15% Due 1/03/08		28,593
	28,100	Hershey Foods (c) 4.22% Due 1/02/08		28,097
	27,900	Nestle Capital (c) 4.24% Due 1/08/08		27,877
	27,700	Chevron Funding 4.21% Due 1/02/08		27,697
	79,722	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by U.S. Government Agency Obligations with various maturities to 5/28/18, market value $81,329 (repurchase proceeds $79,735)		79,722
(Amortized Cost: $310,615)				310,615
Total Investments: 100.6% (Cost: $3,977,444)(d)(e)				5,830,414
Cash and Other Assets Less Liabilities: (0.6)%				(32,086	)
Total Net Assets: 100%			$	5,798,328

See accompanying notes to financial statements.

38

> Notes to Statement of Investments (dollar values in thousands)

(a)  Non-income producing security.

(b)  An affiliate may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in these affiliated companies during the twelve months ended December 31, 2007, are as follows:

Affiliates	Balance of Shares Held 12/31/06		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/07		Value		Dividend
AIN Pharmaciez		643,000		-		-		643,000	$	9,329	$	91
FullCast		-		14,000		-		14,000		8,192		226
Kongsberg Automotive		2,065,000		709,800		-		2,774,800		20,388		386
Unit 4 Agresso		1,150,000		235,000		-		1,385,000		39,345		1,194
Van Houtte*		950,000		-		950,000		-		-		245
TOTAL OF AFFILIATED TRANSACTIONS		4,808,000		958,800		950,000		4,816,800	$	77,254	$	2,142

*  At December 31, 2007, the Fund owned less than five percent of the company's outstanding voting shares.

  The aggregate cost and value of these companies at December 31, 2007, was $89,822 and $77,254 respectively. Investments in affiliate companies represented 1.33% of total net assets at December 31, 2007.

(c)  Security exempt from registration under Section 4(2) of the Securities Act of 1933. These securities may only be resold in exempt transactions to qualified buyers. Private resales of these securities to qualified institutional buyers are also exempt from registration pursuant to Rule 144A under the Securities Act of 1933. At December 31, 2007, these securities had an aggregate value of $145,613, which represented 2.5% of net assets.

(d)  At December 31, 2007, for federal income tax purposes cost of investments was $3,979,936 and net unrealized appreciation was $1,850,478 consisting of gross unrealized appreciation of $2,094,574 and gross unrealized depreciation of $244,096.

(e)  On December 31, 2007, the Fund's total investments were denominated in currencies as follows:

Currency	Value		% of Total Net Assets
Euro	$	1,872,108		32.3	%
Japanese Yen		759,282		13.1
US Dollar		695,355		12.0
Hong Kong Dollar		411,256		7.1
Swiss Franc		315,133		5.4
British Pound		290,960		5.0
Other currencies less than 5% of total net assets		1,486,320		25.7
	$	5,830,414		100.6	%

See accompanying notes to financial statements.

39

Columbia Acorn International

Portfolio Diversification

At December 31, 2007, the Fund's portfolio investments as a percent of net assets were diversified as follows:

	Value (000)		Percent
> Industrial Goods & Services
Industrial Materials & Specialty Chemicals	$	432,819		7.5	%
Other Industrial Services		413,441		7.1
Machinery		276,397		4.8
Conglomerates		203,890		3.5
Electrical Components		144,299		2.5
Outsourcing Services		132,424		2.3
Construction		102,788		1.8
Steel		33,052		0.6
Industrial Distribution		25,878		0.4
		1,764,988		30.5
> Consumer Goods & Services
Other Consumer Services		197,728		3.4
Retail		131,895		2.2
Casinos & Gaming		115,422		2.0
Food & Beverage		105,300		1.8
Other Durable Goods		89,715		1.5
Consumer Goods Distribution		66,384		1.1
Apparel		54,229		1.0
Travel		53,579		0.9
Other Entertainment		50,576		0.9
Nondurables		38,495		0.7
Consumer Electronics		38,411		0.7
Leisure Products		38,333		0.7
Furniture & Textiles		20,083		0.3
		1,000,150		17.2
> Information
Financial Processors		158,842		2.7
Computer Hardware & Related Equipment		128,655		2.2
Satellite Broadcasting & Services		78,666		1.4
Business Information & Marketing Services		76,516		1.3
Internet Related		75,225		1.3
CATV		74,287		1.3
Semiconductors & Related Equipment		59,954		1.0
Publishing		46,964		0.8
Business Software		39,345		0.7
TV Broadcasting		36,721		0.6
Computer Services		32,692		0.6
Instrumentation		15,998		0.3
Advertising		14,413		0.3
Electronics Distribution		14,273		0.2
		852,551		14.7

	Value (000)			Percent
> Energy & Minerals
Oil Services	$	409,814			7.1	%
Mining		196,318			3.4
Oil Refining, Marketing & Distribution		86,819			1.5
Agricultural Commodities		69,650			1.2
Oil & Gas Producers		23,199			0.4
		785,800			13.6
> Finance
Brokerage & Money Management		146,821			2.5
Banks		76,633			1.3
Savings & Loans		71,751			1.3
Insurance		52,860			0.9
Closed End Funds		35,507			0.6
Finance Companies		21,478			0.4
Credit Cards		8,338			0.1
		413,388			7.1
> Other Industries
Transportation		292,702			5.1
Real Estate		75,021			1.3
Regulated Utilities		25,138			0.4
		392,861			6.8
> Health Care
Medical Equipment & Devices		130,417			2.2
Health Care Services		84,957			1.5
Pharmaceuticals		50,975			0.9
Biotechnology & Drug Delivery		25,417			0.4
Medical Supplies		18,295			0.3
		310,061			5.3
Total Equities:		5,519,799			95.2
Short-Term Obligations:		310,615			5.4
Total Investments:		5,830,414			100.6
Cash and Other Assets Less Liabilities:		(32,086	)		(0.6	)
Net Assets:	$	5,798,328			100.0	%

See accompanying notes to financial statements.

40

Columbia Acorn USA

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	09/30/07		12/31/07
Additions
Information
AMIS Holdings		762,300		900,000
Blackbaud		386,406		525,000
Ciena		85,000		125,000
Cogent Communications		0		223,100
Global Payments		393,280		468,280
Informatica		370,000		570,000
IPG Photonics		192,906		425,000
Netgear		97,300		190,000
Plexus		0		115,000
Scientific Games		0		100,000
SRA International		95,000		205,000
Varian		0		45,000
Viad		0		100,000
Consumer Goods & Services
Herman Miller		0		175,000
Thor Industries		80,000		180,000
True Religion Apparel		885,200		950,313
Winnebago		0		150,000
Industrial Goods & Services
Albany International		0		90,000
American Reprographics		196,000		396,000
Donaldson		319,800		394,800
G&K Services		89,000		179,000
Texas Industries		0		50,000
TrueBlue		0		350,000
Vulcan Materials		0		23,589
Health Care
Alexion Pharmaceuticals		0		40,000
Cephalon		50,000		145,000
Illumina		55,000		85,000
Orthofix International		0		111,360
PSS World Medical		470,000		660,000
Energy & Minerals
Carrizo Oil & Gas		245,000		311,193
Finance
Associated Banc-Corp		98,600		213,600
H & E Equipment Services		0		175,000
Lakeland Financial		164,388		289,698
Marlin Business Services		0		100,000
MB Financial		105,000		205,000
Old Second Bancorp		135,000		220,000
Valley National Bancorp		0		108,300
Other Industries
Rush Enterprises		0		177,353

	Number of Shares
	09/30/07		12/31/07
Sales
Information
Ceridian		350,000		0
Discovery Holding		240,000		0
Windstream		240,000		0
Consumer Goods & Services
Scotts Miracle-Gro		531,400		266,000
Industrial Goods & Services
Florida Rock		204,050		0
Genlyte Group		500,000		0
Goodman Global		272,000		0
Labor Ready		350,000		0
Health Care
Edwards Lifesciences		577,400		115,405
LCA-Vision		210,000		0
Medarex		400,000		320,000
Medicis Pharmaceutical		305,000		180,000
Medicure		3,690,300		2,824,700
MGI Pharma		270,000		0
Myriad Genetics		125,000		100,000
Vital Signs		105,000		50,000
Energy & Minerals
Atwood Oceanics		367,000		330,000
Finance
Greene County Bancshares		145,000		130,000
TCF Financial		179,500		149,800
Thomas Weisel Partners Group		189,523		110,923
United America Indemnity		91,000		0
Other Industries
Northeast Utilities		97,500		0

See accompanying notes to financial statements.

41

Columbia Acorn USA

Statement of Investments, December 31, 2007

Number of Shares			Value (000)
				Equities: 99.1%
Information 33.9%
		> Business Software 6.6%
	340,700	Micros Systems (a)	$	23,904
		Information Systems for Restaurants & Hotels
	779,900	Avid Technology (a)		22,102
		Digital Nonlinear Editing Software & Systems
	525,000	Blackbaud		14,721
		Software & Services for Non-profits
	2,100,000	Novell (a)		14,427
		Directory, Operating System & Identity Management Software
	570,000	Informatica (a)		10,271
		Enterprise Data Integration Software
	215,100	ANSYS (a)		8,918
		Simulation Software for Engineers & Designers
	230,400	Concur Technologies (a)		8,343
		Web Enabled Cost & Expense Management Software
				102,686
		> Instrumentation 4.3%
	860,000	Flir Systems (a)		26,918
		Infrared Cameras
	140,000	Mettler Toledo (a)		15,932
		Laboratory Equipment
	368,000	Trimble Navigation (a)		11,128
		GPS-based Instruments
	425,000	IPG Photonics (a)		8,496
		Fiber Lasers
	45,000	Varian (a)		2,938
		Analytical Instruments
	60,000	FARO Technologies (a)		1,631
		Precision Measurement Equipment
				67,043
		> Mobile Communications 4.1%
	1,005,000	Crown Castle International (a)		41,808
		Communications Towers
	506,000	American Tower (a)		21,556
		Communications Towers in USA & Mexico
	88,000	Globalstar (a)		704
		Satellite Mobile Voice & Data Carrier
				64,068
		> Computer Hardware & Related Equipment 4.1%
	505,000	II-VI (a)		15,428
		Laser Components
	433,581	Nice Systems (Israel) (a)		14,881
		Audio & Video Recording Solutions
	295,600	Amphenol		13,707
		Electronic Connectors
	160,000	Belden CDT		7,120
		Specialty Cable
	190,000	Netgear (a)		6,777
		Networking Products for Small Business & Home
	99,000	Zebra Technologies (a)		3,435
		Bar Code Printers

Number of Shares			Value (000)
	65,000	Intermec (a)	$	1,320
		Bar Code & Wireless LAN Systems
	26,000	Rogers (a)		1,128
		PCB Laminates & High-performance Foams
				63,796
		> Semiconductors & Related Equipment 3.7%
	710,000	Microsemi (a)		15,719
		Analog/Mixed-signal Semiconductors
	1,298,490	Integrated Device Technology (a)		14,686
		Communications Semiconductors
	900,000	AMIS Holdings (a)		9,018
		Mixed-signal Semiconductors
	190,000	Littelfuse (a)		6,262
		Little Fuses
	725,000	Entegris (a)		6,257
		Semiconductor Wafer Shipping & Handling Products
	189,296	Supertex (a)		5,923
		Mixed-signal Semiconductors
				57,865
		> Telecommunications Equipment 2.3%
	2,688,200	Tellabs (a)		17,581
		Telecommunications Equipment
	525,000	Polycom (a)		14,584
		Video Conferencing Equipment
	125,000	Ciena (a)		4,264
		Optical Transport & Broadband Access Equipment
				36,429
		> Telephone Services 2.3%
	1,486,000	Time Warner Telecom (a)		30,151
		Fiber Optic Telephone/Data Services
	223,100	Cogent Communications (a)		5,290
		Internet Data Pipelines
				35,441
		> Internet Related 1.9%
	650,000	TheStreet.com		10,348
		Financial Information Website Publisher
	460,000	ValueClick (a)		10,074
		Internet Advertising
	980,000	CNET Networks (a)		8,957
		Internet Advertising on Niche Websites
				29,379
		> Financial Processors 1.4%
	468,280	Global Payments		21,784
		Credit Card Processor
				21,784
		> Computer Services 1.1%
	205,000	SRA International (a)		6,037
		Government IT Services
	1,005,500	AnswerThink		4,867
		IT Integration & Best Practice Research
	786,000	RCM Technologies (a)(b)		4,622
		Technology & Engineering Services
	235,000	iGate (a)		1,990
		IT & Business Process Outsourcing Services
				17,516

See accompanying notes to financial statements.

42

Number of Shares			Value (000)
		> TV Broadcasting 0.5%
	1,125,000	Entravision Communications (a)	$	8,809
		Spanish Language TV, Radio & Outdoor
				8,809
		> Television Programming 0.4%
	750,000	Lions Gate Entertainment (a)		7,065
		Film & TV Studio
				7,065
		> Radio 0.4%
	511,100	Salem Communications		3,368
		Radio Stations for Religious Programming
	300,000	Saga Communications (a)		1,767
		Radio Stations in Small- & Mid-sized Cities
	705,500	Spanish Broadcasting System (a)		1,305
		Spanish Language Radio Stations
				6,440
		> Gaming Equipment & Services 0.3%
	100,000	Scientific Games (a)		3,325
		Lottery Services Provider
	98,500	Shuffle Master (a)		1,181
		Card Shufflers & Casino Games
				4,506
		> Business Information & Marketing Services 0.3%
	100,000	Viad		3,158
		Trade Show Services, Travel & Tours
	98,300	Navigant Consulting (a)		1,344
		Financial Consulting Firm
				4,502
		> Contract Manufacturing 0.2%
	115,000	Plexus (a)		3,020
		Electronic Manufacturing Services
				3,020
Information: Total				530,349
Consumer Goods & Services 18.1%
		> Retail 4.7%
	398,000	Abercrombie & Fitch		31,828
		Teen Apparel Retailer
	540,000	Urban Outfitters (a)		14,720
		Apparel & Home Specialty Retailer
	175,000	J Crew Group (a)		8,437
		Multi-channel Branded Retailer
	224,500	AnnTaylor Stores (a)		5,738
		Women's Apparel Retailer
	486,250	Christopher & Banks		5,568
		Women's Apparel Retailer
	418,000	Chico's FAS (a)		3,775
		Women's Specialty Retailer
	95,000	Genesco (a)		3,591
		Multi-concept Branded Footwear Retailer
	3,800	Lululemon Athletica (a)		180
		Premium Active Apparel Retailer
				73,837
		> Apparel 2.8%
	950,313	True Religion Apparel (a)		20,289
		Premium Denim

Number of Shares			Value (000)
	634,200	Oxford Industries	$	16,343
		Branded & Private Label Apparel
	222,200	Coach (a)		6,795
		Designer & Retailer of Branded Leather Accessories
				43,427
		> Other Consumer Services 2.8%
	366,000	ITT Educational Services (a)		31,209
		Post-secondary Degree Services
	310,000	Universal Technical Institute (a)		5,270
		Vocational Training
	149,000	NutriSystem (a)		4,020
		Weight Loss Programs
	60,000	Weight Watchers International		2,711
		Weight Loss Programs
				43,210
		> Other Durable Goods 1.9%
	2,078,300	Champion Enterprises (a)		19,578
		Manufactured Homes
	287,900	Cavco Industries (a)		9,742
		Higher End Manufactured Homes
				29,320
		> Leisure Products 1.8%
	301,300	International Speedway		12,408
		Largest Motorsports Racetrack Owner & Operator
	180,000	Thor Industries		6,842
		RV & Bus Manufacturer
	195,500	Speedway Motorsports		6,076
		Motorsports Racetrack Owner & Operator
	150,000	Winnebago		3,153
		Premier Motorhome Maker
				28,479
		> Restaurants 0.8%
	337,500	Sonic (a)		7,391
		Quick Service Restaurant
	163,800	Red Robin Gourmet Burgers (a)		5,240
		Casual Dining Restaurant
				12,631
		> Nondurables 0.8%
	266,000	Scotts Miracle-Gro		9,954
		Consumer Lawn & Garden Products
	108,000	Jarden (a)		2,550
		Branded Household Products
				12,504
		> Furniture & Textiles 0.8%
	400,000	Knoll		6,572
		Office Furniture
	175,000	Herman Miller		5,668
		Office Furniture
				12,240
		> Casinos & Gaming 0.7%
	455,000	Pinnacle Entertainment (a)		10,720
		Regional Casino Operator
				10,720

See accompanying notes to financial statements.

43

Columbia Acorn USA

Statement of Investments, continued

Number of Shares			Value (000)
		> Consumer Goods Distribution 0.7%
	523,500	Pool	$	10,381
		Distributor of Swimming Pool Supplies & Equipment
				10,381
		> Food & Beverage 0.2%
	90,000	Hansen Natural (a)		3,986
		Alternative Beverages
				3,986
		> Travel 0.1%
	45,000	Vail Resorts (a)		2,421
		Ski Resort Operator & Developer
				2,421
Consumer Goods & Services: Total				283,156
Industrial Goods & Services 12.9%
		> Machinery 8.3%
	697,500	Ametek		32,671
		Aerospace/Industrial Instruments
	650,300	ESCO Technologies (a)		25,973
		Automatic Electric Meter Readers
	673,600	Pentair		23,448
		Pumps & Water Treatment
	373,600	Nordson		21,654
		Dispensing Systems for Adhesives & Coatings
	394,800	Donaldson		18,311
		Industrial Air Filtration
	71,800	Toro		3,909
		Turf Maintenance Equipment
	50,000	Kaydon		2,727
		Specialized Friction & Motion Control Products
	21,823	MOOG (a)		999
		Motion Control Products for Aerospace, Defense & Industrial Markets
				129,692
		> Other Industrial Services 1.6%
	415,000	American Commercial Lines (a)		6,740
		Operator/Builder of Inland Barges
	179,000	G&K Services		6,716
		Uniform Rental
	396,000	American Reprographics (a)		6,526
		Document Management & Logistics
	350,000	TrueBlue (a)		5,068
		Temporary Manual Labor
				25,050
		> Outsourcing Services 0.9%
	350,000	Quanta Services (a)		9,184
		Electrical & Telecom Construction Services
	175,000	Administaff		4,949
		Professional Employer Organization
				14,133
		> Construction 0.6%
	50,000	Texas Industries		3,505
		Aggregates, Cement & Concrete
	100,000	Simpson Manufacturing		2,659
		Wall Joint Maker

Number of Shares			Value (000)
	23,589	Vulcan Materials	$	1,865
		Aggregates, Concrete & Asphalt
	140,000	M/I Homes		1,470
		Home Builder
				9,499
		> Waste Management 0.5%
	280,875	Waste Connections (a)		8,679
		Solid Waste Management
				8,679
		> Industrial Materials & Specialty Chemicals 0.5%
	155,000	Drew Industries (a)		4,247
		RV & Manufactured Home Components
	90,000	Albany International		3,339
		Paper Machine Clothing & Advanced Textiles
				7,586
		> Industrial Distribution 0.5%
	225,000	Interline Brands (a)		4,930
		Industrial Distribution
	70,000	Watsco		2,573
		HVAC Distribution
				7,503
Industrial Goods & Services: Total				202,142
Health Care 11.6%
		> Biotechnology & Drug Delivery 5.1%
	700,000	BioMarin (a)		24,780
		Biotech Focused on Orphan Diseases
	885,000	PDL BioPharma (a)		15,505
		Proprietary Monoclonal Antibodies
	421,400	Seattle Genetics (a)		4,804
		Antibody-based Therapies for Cancer
	100,000	Myriad Genetics (a)		4,642
		Drugs/Diagnostics Hybrid
	545,000	Array Biopharma (a)		4,589
		Drugs for Cancer & Inflammatory Diseases
	1,135,000	Decode Genetics (a)		4,177
		Drugs for Heart Attack, Asthma & Vascular Disease
	580,000	Nektar Therapeutics (a)		3,892
		Drug Delivery Technologies
	320,000	Medarex (a)		3,334
		Humanized Antibodies
	401,000	Arena Pharmaceuticals (a)		3,140
		Novel Drug Targeting Technology
	40,000	Alexion Pharmaceuticals (a)		3,001
		Biotech Focused on Orphan Diseases
	2,824,700	Medicure (a)		2,825
	738,060	Medicure - Warrants (a)(c)		295
		Cardiovascular Biotech Company
	400,000	Neurogen (a)		1,380
		Development-stage Biotech Focused on Neurology
	220,000	Pharmacopeia (a)		1,049
		Biotech Company with Broad Early-stage Pipeline

See accompanying notes to financial statements.

44

Number of Shares			Value (000)
		> Biotechnology & Drug Delivery—continued
	500,000	IsoRay (a)	$	990
	100,000	IsoRay - Warrants (a)(c)		5
		Radiology Cancer Company
	273,500	Nuvelo (a)		501
		Development-stage Biotech Focused on Cardiovascular/Cancer
	57,499	La Jolla Pharmaceutical (a)		225
		Lupus Treatment
	37,500	Locus Pharmaceuticals, Series A-1, Pfd. (a)(c)		98
	19,329	Locus Pharmaceuticals, Series B-1, Pfd. (a)(c)		50
		High Throughput Rational Drug Design
	18,181	Metabolex, Series F (a)(c)		30
		Diabetes Drug Development
				79,312
		> Health Care Services 2.0%
	660,000	PSS World Medical (a)		12,916
		Medical Supplies
	291,800	Lincare Holdings (a)		10,260
		Home Health Care Services
	137,000	Charles River Laboratories (a)		9,014
		Pharmaceutical Research
				32,190
		> Pharmaceuticals 1.6%
	145,000	Cephalon (a)		10,405
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	180,000	Medicis Pharmaceutical		4,674
		Specialty Pharmaceuticals for Dermatology
	1,040,000	QLT (a)		4,597
		Specialty Pharmaceuticals for Ophthalmology & Dermatology
	300,000	Collagenex Pharmaceuticals (a)		2,865
		Specialty Pharmaceuticals for Dermatology
	505,000	Barrier Therapeutics (a)		1,990
		Specialty Pharmaceuticals for Dermatology
				24,531
		> Medical Supplies 1.5%
	158,300	Techne (a)		10,456
		Cytokines, Antibodies & other Reagents for Life Science
	270,700	ICU Medical (a)		9,748
		Intravenous Therapy Products
	200,000	QIAGEN (Netherlands) (a)		4,210
		Life Science Company; DNA/RNA Purification
				24,414
		> Medical Equipment & Devices 1.4%
	111,360	Orthofix International (a)		6,456
		Bone Fixation & Stimulation Devices
	115,405	Edwards Lifesciences (a)		5,307
		Heart Valves
	85,000	Illumina (a)		5,037
		Leading Tools & Service Provider for Genetic Analysis
	50,000	Vital Signs		2,556
		Anesthesia, Respiratory & Sleep Products

Number of Shares			Value (000)
	94,171	Advanced Medical Optics (a)	$	2,310
		Medical Devices for Eye Care
				21,666
Health Care: Total				182,113
Energy & Minerals 11.2%
		> Oil Services 6.3%
	803,400	FMC Technologies (a)		45,553
		Oil & Gas Wellhead Manufacturer
	330,000	Atwood Oceanics (a)		33,079
		Offshore Drilling Contractor
	115,375	Exterran Holdings (a)		9,438
		Natural Gas Compressor Rental & Fabrication
	241,000	Tetra Technologies (a)		3,752
		U.S. Based Service Company with Life of Field Approach
	129,000	Tesco (a)		3,698
		Developing New Well Drilling Technologies
	59,800	CARBO Ceramics		2,225
		Natural Gas Well Stimulants
				97,745
		> Oil & Gas Producers 4.1%
	525,000	Quicksilver Resources (a)		31,285
		Natural Gas & Coal Seam Gas Producer
	311,193	Carrizo Oil & Gas (a)		17,038
		Explores for Natural Gas & Crude Oil
	138,400	Southwestern Energy (a)		7,711
		Oil & Gas Producer
	111,200	Equitable Resources		5,925
		Natural Gas Producer & Utility
	450,000	Vaalco Energy (a)		2,092
		Oil & Gas Producer
				64,051
		> Other Resources 0.7%
	218,000	Layne Christensen (a)		10,728
		Oil & Gas Production/Engineering & Construction/Contract Drilling
				10,728
		> Oil Refining, Marketing & Distribution 0.1%
	50,250	Oneok		2,250
		Natural Gas Distribution, Pipeline Processing & Trading
				2,250
Energy & Minerals: Total				174,774
Finance 9.4%
		> Banks 3.4%
	212,756	Chittenden		7,578
		New England Bank
	205,000	MB Financial		6,320
		Chicago Bank
	289,698	Lakeland Financial		6,055
		Indiana Bank
	220,000	Old Second Bancorp		5,894
		Illinois Bank

See accompanying notes to financial statements.

45

Columbia Acorn USA

Statement of Investments, continued

Number of Shares			Value (000)
		> Banks—continued
	213,600	Associated Banc-Corp	$	5,786
		Midwest Bank
	280,777	Glacier Bancorp		5,262
		Mountain States Bank
	408,000	Pacific Continental		5,084
		Niche Pacific N.W. Bank
	215,000	First Busey		4,270
		Illinois Bank
	149,800	TCF Financial		2,686
		Great Lakes Bank
	130,000	Greene County Bancshares		2,496
		Tennessee Bank
	108,300	Valley National Bancorp		2,064
		New Jersey/New York Bank
	15,000	West Bancorporation		196
		Des Moines Commercial Bank
				53,691
		> Insurance 2.7%
	714,500	HCC Insurance Holdings		20,492
		Specialty Insurance
	14,000	Markel (a)		6,875
		Specialty Insurance
	105,000	Philadelphia Consolidated Holding (a)		4,132
		Specialty Insurance
	75,000	Endurance Specialty Holdings		3,130
		Commercial Lines Insurance/Reinsurance
	87,000	Delphi Financial Group		3,069
		Group Employee Benefit Products & Services
	166,593	Eastern Insurance Holdings		2,742
		Workers Comp. & Specialty Insurance
	200,000	Meadowbrook Insurance Group (a)		1,882
		Specialty Insurance Products & Services
				42,322
		> Finance Companies 2.5%
	1,136,500	AmeriCredit (a)		14,536
		Auto Lending
	482,900	World Acceptance (a)		13,029
		Personal Loans
	130,000	McGrath Rentcorp		3,347
		Temporary Space & IT Rentals
	175,000	H & E Equipment Services (a)		3,304
		Heavy Equipment Leasing
	140,000	Aaron Rents		2,694
		Rent-to-own
	100,000	Marlin Business Services (a)		1,206
		Small Equipment Leasing
	66,953	Electro Rent		994
		Test & Measurement Rentals
				39,110
		> Brokerage & Money Management 0.4%
	150,000	SEI Investments		4,825
		Mutual Fund Administration & Investment Management
	110,923	Thomas Weisel Partners Group (a)		1,523
		Boutique Bay Area Investment Bank
				6,348

Number of Shares or Principal Amount (000)			Value (000)
		> Savings & Loans 0.4%
	258,000	People's United	$	4,592
		Connecticut Savings & Loan
	46,200	Anchor Bancorp Wisconsin		1,087
		Wisconsin Thrift
				5,679
Finance: Total				147,150
Other Industries 2.0%
		> Real Estate 1.3%
	560,000	DiamondRock Hospitality		8,389
		Hotel Owner
	100,000	Digital Realty Trust		3,837
		Technology-focused Office Buildings
	77,500	Gaylord Entertainment (a)		3,136
		Convention Hotels
	90,000	American Campus Communities		2,416
		Student Housing
	150,000	Kite Realty Group		2,291
		Community Shopping Centers
				20,069
		> Transportation 0.7%
	524,720	Heartland Express		7,441
		Regional Trucker
	177,353	Rush Enterprises (a)		3,224
		Truck Distribution
				10,665
Other Industries: Total				30,734
Total Equities: 99.1% (Cost: $1,208,449)				1,550,418
Short-Term Obligations 2.2%
$	8,100	Toyota Motor Credit 4.18% Due 1/02/08		8,099
	25,801	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by a U.S. Government Agency Obligation, maturing 2/06/17, market value $26,322 (repurchase proceeds $25,805)		25,801
		(Amortized Cost: $33,900)		33,900
Total Investments: 101.3% (Cost: $1,242,349)(d)				1,584,318
Cash and Other Assets Less Liabilities: (1.3)%				(20,376	)
Total Net Assets: 100%			$	1,563,942

See accompanying notes to financial statements.

46

> Notes to Statement of Investments (dollar values in thousands)

(a)  Non-income producing security.

(b)  An affiliate may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in this affiliated company during the twelve months ended December 31, 2007, are as follows:

Affiliates	Balance of Shares Held 12/31/06		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/07		Value		Dividend
RCM Technologies		786,000		-		-		786,000	$	4,622	$	-

  The aggregate cost and value of these companies at December 31, 2007, was $5,636 and $4,622 respectively. Investments in affiliate companies represented 0.30% of total net assets at December 31, 2007.

(c)  Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued in good faith by the board of trustees. At December 31, 2007, these securities amounted to $478 which represented 0.03% of total net assets.

  Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Locus Pharmaceuticals, Series A-1 Pfd.	9/5/01		37,500	$	1,500	$	98
Locus Pharmaceuticals, Series B-1 Pfd.	2/8/07		19,329		56		50
Metabolex, Series F	5/11/00		18,181		2,000		30
IsoRay - Warrants	3/21/07		100,000		-		5
Medicure - Warrants	12/22/06		738,060		-		295
				$	3,556	$	478

(d)  At December 31, 2007, for federal income tax purposes cost of investments was $1,242,593 and net unrealized appreciation was $341,725 consisting of gross unrealized appreciation of $494,581 and gross unrealized depreciation of $152,856.

See accompanying notes to financial statements.

47

Columbia Acorn International Select

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	09/30/07		12/31/07
Additions
Europe
> Netherlands
Fugro		143,500		170,000
QIAGEN		135,000		170,000
> United Kingdom
Informa Group		370,000		470,000
Intertek Testing		135,000		310,000
> Ireland
United Drug		959,600		1,100,000
> Sweden
Hexagon		360,000		390,000
Securitas Systems		857,000		1,030,000
> France
SES Global		343,000		370,000
Asia
> Japan
Hoya		188,000		215,000
Ibiden		70,000		75,000
> China
China Shipping Development		1,250,000		1,795,000
Jiangsu Expressway		2,500,000		5,500,000
Lenovo Group		7,300,000		8,600,000
VisionChina Media		0		53,000
Other Countries
> United States
Diamond Offshore		55,000		60,000
> South Africa
Impala Platinum Holdings		203,000		215,000
Uranium One		0		400,000
> Canada
Petro Rubiales Energy-Warrants		0		343,200
> Australia
Sino Gold		303,259		1,256,000
Latin America
> Brazil
BM&F		0		101,000
Bovespa		0		140,400

	Number of Shares
	09/30/07		12/31/07
Sales
Europe
> Netherlands
USG People		29,000		0
> Switzerland
Geberit		20,500		0
Nobel Biocare Holding		23,000		10,000
> Ireland
CRH		132,037		75,000
> Germany
Deutsche Boerse		19,500		15,000
Asia
> Japan
Nintendo		20,000		16,500
Park24		350,000		0
Ushio		76,500		0
> Hong Kong
Hong Kong Exchanges and Clearing		299,000		215,000
Other Countries
> Canada
Potash Corp. of Saskatchewan		90,000		59,400

See accompanying notes to financial statements.

48

Columbia Acorn International Select

Statement of Investments, December 31, 2007

Number of Shares			Value (000)
				Equities: 91.5%
Europe 47.3%
		> Netherlands 9.6%
	170,000	Fugro	$	13,031
		Oilfield Services
	170,000	QIAGEN (a)		3,651
		Life Science Company; DNA/RNA Purification
	142,000	Aalberts Industries		2,799
		Flow Control & Heat Treatment
	87,000	SBM Offshore		2,729
		Builds & Leases Offshore Vessels to Process & Store Crude Oil
	76,700	OPG Groep		2,119
		Health Care Supplies & Pharmacies
	23,100	Boskalis Westminster		1,403
		Dredging & Maritime Contractor
	74,000	Wavin		979
		Largest European Plastic Pipe Systems Company
				26,711
		> Switzerland 7.0%
	75,000	Kuehne & Nagel		7,150
		Freight Forwarding/Logistics
	45,000	Synthes		5,562
		Products for Orthopedic Surgery
	10,000	Nobel Biocare Holding		2,645
		Dental Implants & Ceramic Crowns
	7,500	Swatch Group		2,249
		Watch & Electronics Manufacturer
	26,000	Schindler		1,662
		Elevator Manufacturer & Service Provider
				19,268
		> United Kingdom 6.4%
	650,000	Smith & Nephew		7,473
		Medical Equipment & Supplies
	310,000	Intertek Testing		6,078
		Testing, Inspection, Certification Services
	470,000	Informa Group		4,299
		Global Publisher & Event Organizer
				17,850
		> Ireland 4.9%
	1,100,000	United Drug		6,343
		Irish Pharmaceutical Wholesaler & Outsourcer
	205,000	IAWS Group		4,538
		Baked Goods
	75,000	CRH		2,604
		Global Building Materials
				13,485
		> Sweden 4.2%
	390,000	Hexagon		8,042
		Measurement Equipment & Polymers
	1,030,000	Securitas Systems		3,634
		Commercial Security Installation & Service
				11,676

Number of Shares			Value (000)
		> France 3.5%
	370,000	SES Global	$	9,702
		Satellite Broadcasting Services
				9,702
		> Germany 3.3%
	40,000	Wincor Nixdorf		3,769
		Retail POS Systems & ATM Machines
	15,000	Deutsche Boerse		2,961
		Trading, Clearing, Settlement Services for Financial Markets
	1,250	Porsche		2,519
		Specialty Automobile Manufacturer
				9,249
		> Austria 2.6%
	200,000	Zumtobel		7,179
		Lighting Systems
				7,179
		> Greece 2.5%
	350,000	Intralot		6,897
		Lottery & Gaming Systems & Services
				6,897
		> Spain 2.0%
	55,000	Red Electrica de Espana		3,457
		Spanish Power Grid
	110,000	Prisa		2,045
		Leading Spanish-speaking Publisher
				5,502
		> Denmark 1.3%
	31,000	Novozymes		3,499
		Industrial Enzymes
				3,499
Europe: Total				131,018
Asia 24.4%
		> Japan 13.2%
	16,500	Nintendo		10,018
		Entertainment Software & Hardware
	8,500	Jupiter Telecommunications (a)		7,191
		Largest Cable Service Provider in Japan
	215,000	Hoya		6,862
		Opto-electrical Components & Eyeglass Lenses
	75,000	Ibiden		5,180
		Electronic Parts & Ceramics
	600,000	Kansai Paint		4,352
		Paint Producer in Japan, India, China & Southeast Asia
	1,800	Kenedix		2,896
		Real Estate Investment Management
				36,499
		> China 6.7%
	8,600,000	Lenovo Group		7,604
		Third Largest PC Vendor Globally
	5,500,000	Jiangsu Expressway		5,935
		Chinese Toll Road Operator

See accompanying notes to financial statements.

49

Columbia Acorn International Select

Statement of Investments, continued

Number of Shares			Value (000)
		> China—continued
	1,795,000	China Shipping Development	$	4,681
		China's Dominant Shipper for Oil & Coal
	53,000	VisionChina Media (a)		451
		Advertising on Digital Screens in China's Mass Transit System
				18,671
		> Hong Kong 2.2%
	215,000	Hong Kong Exchanges and Clearing		6,036
		Hong Kong Equity & Derivatives Market Operator
				6,036
		> Singapore 1.2%
	364,000	Singapore Exchange		3,327
		Singapore Equity & Derivatives Market Operator
				3,327
		> South Korea 1.1%
	105,200	Sung Kwang Bend		3,019
		A Large Customized Industrial Pipe Fitting Manufacturer
				3,019
Asia: Total				67,552
Other Countries 18.3%
		> South Africa 5.7%
	215,000	Impala Platinum Holdings		7,417
		Platinum Group Metals Mining & Refining
	198,000	Naspers		4,661
		Media & Education in Africa & other Emerging Markets
	400,000	Uranium One (a)		3,578
		Uranium Mines in South Africa, Kazakhstan, Australia & the U.S.
				15,656
		> Canada 5.2%
	59,400	Potash Corp. of Saskatchewan		8,551
		World's Largest Producer of Potash
	2,000,000	Petro Rubiales Energy (Canada) (a)(b)		2,914
	828,400	Petro Rubiales Energy - Warrants (Canada) (a)(b)		457
		Oil Production & Exploration in Colombia
	137,000	RONA (a)		2,367
		Leading Canadian Do-it-yourself Retailer
				14,289
		> United States 4.7%
	60,000	Diamond Offshore		8,520
		Contract Driller
	45,500	Atwood Oceanics (a)		4,561
		Offshore Drilling Contractor
				13,081

Number of Shares or Principal Amount (000)			Value (000)
		> Australia 2.7%
	1,256,000	Sino Gold (a)	$	7,601
		Gold Mining in The People's Republic of China
				7,601
Other Countries: Total				50,627
Latin America 1.5%
		> Brazil 1.5%
	140,400	Bovespa (a)		2,705
		Brazil Equity & Derivative Exchange
	101,000	BM&F (a)		1,419
		Brazilian Derivatives Exchange
				4,124
Latin America: Total				4,124
Total Equities: 91.5% (Cost: $198,448)				253,321
Short-Term Obligation 4.4%
$	12,288	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by a U.S. Government Agency Obligation, maturing 7/18/16, market value $12,537 (repurchase proceeds $12,290)		12,288
		(Cost: $12,288)		12,288
Total Investments: 95.9% (Cost: $210,736)(c)(d)				265,609
Cash and Other Assets Less Liabilities: (e) 4.1%				11,408
Total Net Assets: 100%			$	277,017

See accompanying notes to financial statements.

50

> Notes to Statement of Investments (dollar values in thousands)

(a)  Non-income producing security.

(b)  Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued in good faith by the board of trustees. At December 31, 2007, these securities amounted to $2,867 which represented 1.04% of total net assets.

  Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Petro Rubiales Energy	7/12/07		1,656,800	$	1,109	$	2,410
Petro Rubiales Energy - Warrants	7/12/07		828,400		236		457
				$	1,345	$	2,867

(c)  At December 31, 2007, for federal income tax purposes cost of investments was $210,962 and net unrealized appreciation was $54,647 consisting of gross unrealized appreciation of $65,182 and gross unrealized depreciation of $10,535.

(d)  On December 31, 2007, the Fund's total investments were denominated in currencies as follows:

Currency	Value		% of Net Assets
Euro	$	78,724		28.4	%
Japanese Yen		36,499		13.2
US Dollar		34,371		12.4
Hong Kong Dollar		24,256		8.8
Swiss Franc		19,269		7.0
British Pound		17,850		6.4
Other currencies less than 5% of total net assets		54,640		19.7
	$	265,609		95.9	%

(e)  Included in Cash and Other Assets Less Liabilities is $12,808 of Japanese Yen.

See accompanying notes to financial statements.

51

Columbia Acorn International Select

Portfolio Diversification

At December 31, 2007, the Fund's portfolio investments as a percent of net assets were diversified as follows:

	Value (000)		Percent
> Information
Financial Processors	$	12,324		4.4	%
Computer Hardware & Related Equipment		11,373		4.1
Consumer Software		10,018		3.6
Satellite Broadcasting & Services		9,702		3.5
CATV		7,191		2.6
Semiconductors & Related Equipment		6,862		2.5
Publishing		6,344		2.3
TV Broadcasting		4,661		1.7
Advertising		451		0.2
		68,926		24.9
> Energy & Minerals
Oil Services		30,243		11.0
Mining		27,148		9.8
Oil & Gas Producers		3,371		1.2
		60,762		22.0
> Industrial Goods & Services
Conglomerates		16,021		5.8
Other Industrial Services		14,890		5.4
Industrial Materials & Specialty Chemicals		8,830		3.2
Electrical Components		7,179		2.6
Outsourcing Services		3,634		1.3
Machinery		3,019		1.1
Construction		2,604		0.9
		56,177		20.3

	Value (000)		Percent
> Health Care
Medical Equipment & Devices	$	15,680		5.7	%
Pharmaceuticals		6,343		2.3
Medical Supplies		3,651		1.3
Health Care Services		2,119		0.7
		27,793		10.0
> Consumer Goods & Services
Casinos & Gaming		6,897		2.5
Other Durable Goods		4,768		1.7
Food & Beverage		4,538		1.6
Retail		2,367		0.9
		18,570		6.7
> Other Industries
Transportation		10,616		3.8
Regulated Utilities		3,457		1.3
Real Estate		2,896		1.0
		16,969		6.1
> Finance
Brokerage & Money Management		4,124		1.5
		4,124		1.5
Total Equities:		253,321		91.5
Short-Term Obligations:		12,288		4.4
Total Investments:		265,609		95.9
Cash and Other Assets Less Liabilities:		11,408		4.1
Net Assets:	$	277,017		100.0	%

See accompanying notes to financial statements.

52

Columbia Acorn Select

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	09/30/07		12/31/07
Additions
Consumer Goods & Services
Chico's FAS		3,100,000		3,500,000
Knoll		0		1,370,000
Information
Cardtronics		0		2,308,000
Globalstar		6,000,000		6,866,316
Novell		6,900,000		7,250,000
Sanmina-SCI		27,500,000		36,700,000
Tellabs		15,000,000		17,000,000
VisionChina Media (China)		0		1,675,000
Energy & Minerals
Tetra Technologies		5,000,000		5,550,000
Uranium One (South Africa)		17,215,800		18,000,000
Finance
Bovespa (Brazil)		0		661,600
Conseco		8,300,000		9,700,000
Janus Capital Group		4,100,000		4,150,000
Industrial Goods & Services
American Commercial Lines		2,450,000		3,000,000
American Reprographics		0		1,000,000

	Number of Shares
	09/30/07		12/31/07
Sales
Information
Canadian Solar		2,700,000		2,400,000
Discovery Holding		3,000,000		2,500,000
Liberty Global, Series A		600,000		0
Liberty Global, Series C		3,000,000		0
Energy & Minerals
Potash Corp. of Saskatchewan (Canada)		1,440,000		1,370,000

See accompanying notes to financial statements.

53

Columbia Acorn Select

Statement of Investments, December 31, 2007

Number of Shares			Value (000)
				Equities: 94.9%
Consumer Goods & Services 25.6%
		> Retail 11.2%
	1,650,000	Abercrombie & Fitch	$	131,950
		Teen Apparel Retailer
	3,550,000	Safeway		121,446
		Supermarkets
	850,000	Costco Wholesale		59,296
		Warehouse Superstores
	3,500,000	Chico's FAS (a)		31,605
		Women's Specialty Retailer
				344,297
		> Travel 4.7%
	3,550,000	Expedia (a)		112,251
		Online Travel Services Company
	2,000,000	Hertz (a)		31,780
		Largest U.S. Rental Car Operator
				144,031
		> Other Consumer Services 4.4%
	1,300,000	ITT Educational Services (a)		110,851
		Post-secondary Degree Services
	1,500,000	Universal Technical Institute (a)(b)		25,500
		Vocational Training
				136,351
		> Leisure Products 2.2%
	800,000	Harley-Davidson		37,368
		Motorcycles & Related Merchandise
	750,000	International Speedway		30,885
		Largest Motorsports Racetrack Owner & Operator
				68,253
		> Furniture & Textiles 1.6%
	850,000	Herman Miller		27,532
		Office Furniture
	1,370,000	Knoll		22,509
		Office Furniture
				50,041
		> Apparel 1.5%
	1,550,000	Coach (a)		47,399
		Designer & Retailer of Branded Leather Accessories
				47,399
Consumer Goods & Services: Total				790,372
Information 23.1%
		> Mobile Communications 4.9%
	2,300,000	American Tower (a)		97,980
		Communications Towers in USA & Mexico
	6,866,316	Globalstar (a)(b)		54,931
		Satellite Mobile Voice & Data Carrier
				152,911
		> Business Software 3.8%
	2,350,000	Avid Technology (a)(b)		66,599
		Digital Nonlinear Editing Software & Systems

Number of Shares			Value (000)
	7,250,000	Novell (a)	$	49,807
		Directory, Operating System & Identity Management Software
				116,406
		> Telecommunications Equipment 3.6%
	17,000,000	Tellabs (a)		111,180
		Telecommunications Equipment
				111,180
		> Internet Related 3.0%
	9,600,000	SkillSoft (a)(b)		91,776
		Web-based Learning Solutions (E-Learning)
				91,776
		> Semiconductors & Related Equipment 2.2%
	2,400,000	Canadian Solar (a)(b)		67,560
		Solar Cell & Module Manufacturer
				67,560
		> Contract Manufacturing 2.2%
	36,700,000	Sanmina-SCI (a)(b)		66,794
		Electronic Manufacturing Services
				66,794
		> CATV 2.0%
	2,500,000	Discovery Holding (a)		62,850
		CATV Programming
				62,850
		> Financial Processors 0.7%
	2,308,000	Cardtronics (a)(b)		23,334
		Operates the World's Largest Network of ATMs
				23,334
		> Advertising 0.5%
	1,675,000	VisionChina Media (China) (a)		14,238
		Advertising on Digital screens in China's Mass Transit System
				14,238
		> Computer Services 0.2%
	1,367,000	AnswerThink (a)		6,616
		IT Integration & Best Practice Research
				6,616
Information: Total				713,665
Energy & Minerals 20.8%
		> Mining 11.6%
	1,370,000	Potash Corp. of Saskatchewan (Canada)		197,225
		World's Largest Producer of Potash
	18,000,000	Uranium One (South Africa) (a)		161,042
		Uranium Mines in South Africa, Kazakhstan, Australia & the U.S.
				358,267
		> Oil Services 6.5%
	5,550,000	Tetra Technologies (a)(b)		86,413
		U.S. Based Service Company with Life of Field Approach
	1,200,000	FMC Technologies (a)		68,040
		Oil & Gas Wellhead Manufacturer

See accompanying notes to financial statements.

54

Number of Shares			Value (000)
		> Oil Services—continued
	300,000	Atwood Oceanics (a)	$	30,072
		Offshore Drilling Contractor
	125,000	Diamond Offshore		17,750
		Contract Driller
				202,275
		> Oil & Gas Producers 2.7%
	50,000,000	Petro Rubiales Energy (Canada) (a)(b)(c)		72,726
	17,212,500	Petro Rubiales Energy-Warrants (Canada) (a)(b)(c)		9,496
		Oil Production & Exploration in Colombia
				82,222
Energy & Minerals: Total				642,764
Finance 13.6%
		> Insurance 7.1%
	9,700,000	Conseco (a)(b)		121,832
		Life, Long-term Care & Medical Supplement Insurance
	112,000	Markel (a)		55,003
		Specialty Insurance
	2,400,000	Montpelier Re		40,824
		Commercial Lines Insurance/Reinsurance
				217,659
		> Brokerage & Money Management 6.5%
	4,150,000	Janus Capital Group		136,327
		Manages Mutual Funds
	1,600,000	SEI Investments		51,472
		Mutual Fund Administration & Investment Management
	661,600	Bovespa (Brazil) (a)		12,749
		Brazil Equity & Derivative Exchange
				200,548
Finance: Total				418,207
Industrial Goods & Services 9.5%
		> Other Industrial Services 4.2%
	1,425,000	Expeditors International of Washington		63,669
		International Freight Forwarder
	3,000,000	American Commercial Lines (a)(b)		48,720
		Operator/Builder of Inland Barges
	1,000,000	American Reprographics (a)		16,480
		Document Management & Logistics
				128,869
		> Outsourcing Services 2.4%
	2,800,000	Quanta Services (a)		73,472
		Electrical & Telecom Construction Services
				73,472
		> Waste Management 1.6%
	1,500,000	Waste Management		49,005
		U.S. Garbage Collection & Disposal
				49,005

Number of Shares or Principal Amount (000)			Value (000)
		> Steel 1.3%
	2,350,000	Worthington Industries	$	42,018
		Steel Processing & Manufactured Metal Products
				42,018
Industrial Goods & Services: Total				293,364
Health Care 1.2%
		> Health Care Services 1.2%
	1,000,000	Lincare Holdings (a)		35,160
		Home Health Care Services
				35,160
Health Care: Total				35,160
Other Industries 1.1%
		> Transportation 1.1%
	1,250,000	JB Hunt Transport Services		34,437
		Truck & Intermodal Carrier
				34,437
Other Industries: Total				34,437
Total Equities: 94.9% (Cost: $2,194,475)				2,927,969
Short-Term Obligations 5.0%
$	15,600	General Electric Capital 4.18% Due 1/08/08		15,587
	15,500	Parker-Hannifin (d) 4.45% Due 1/25/08		15,454
	15,400	Chevron Funding 4.11% Due 1/04/08		15,395
	15,400	Toyota Motor Credit 4.15% Due 1/07/08		15,389
	15,300	Emerson Electric (d) 4.18% Due 1/16/08		15,274
	15,300	United Parcel Services (d) 3.98% Due 1/17/08		15,273
	14,900	Hershey Foods (d) 4.22% Due 1/02/08		14,898
	14,900	IBM Corporation (d) 4.24% Due 1/03/08		14,897
	31,023	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by a U.S. Government Agency Obligation, maturing 7/18/16, market value $31,649 (repurchase proceeds $31,028)		31,023
		(Amortized Cost: $153,190)		153,190
Total Investments: 99.9% (Cost: $2,347,665)(e)				3,081,159
Cash and Other Assets Less Liabilities: 0.1%				4,000
Total Net Assets: 100%			$	3,085,159

See accompanying notes to financial statements.

55

Columbia Acorn Select

Statement of Investments, continued

> Notes to Statement of Investments (dollar values in thousands)

(a)  Non-income producing security.

(b)  An affiliate may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in affiliated companies during the twelve months ended December 31, 2007, are as follows:

Affiliates	Balance of Shares Held 12/31/06		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/07		Value		Dividend
American Commercial Lines		-		3,000,000		-		3,000,000	$	48,720	$	-
Avid Technology		2,200,000		150,000		-		2,350,000		66,599		-
Canadian Solar		550,000		2,150,000		300,000		2,400,000		67,560		-
Cardtronics		-		2,308,000		-		2,308,000		23,334		-
Conseco		2,000,000		7,700,000		-		9,700,000		121,832		-
Globalstar		1,600,000		5,266,316		-		6,866,316		54,931		-
Petro Rubiales Energy		-		50,000,000		-		50,000,000		72,726		-
Petro Rubiales Energy-Warrants		-		17,212,500		-		17,212,500		9,496		-
Sanmina-SCI		10,330,000		26,370,000		-		36,700,000		66,794		-
SkillSoft		9,600,000		-		-		9,600,000		91,776		-
Tetra Technologies		-		5,550,000		-		5,550,000		86,413		-
Universal Technical Institute		1,350,000		150,000		-		1,500,000		25,500		-
UrAsia Energy (merged into Uranium One)*		30,050,000		2,000,000		32,050,000		-		-		-
TOTAL OF AFFILIATED TRANSACTIONS		57,680,000		121,856,816		32,350,000		147,186,816	$	735,681	$	-

*  At December 31, 2007, the Fund owned less than five percent of the company's outstanding voting shares.

  The aggregate cost and value of these companies at December 31, 2007, was $820,725 and $735,681 respectively. Investments in affiliate companies represented 23.8% of total net assets at December 31, 2007.

(c)  Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued in good faith by the board of trustees. At December 31, 2007, these securities amounted to $82,075 which represented 2.66% of net assets.

  Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Petro Rubiales Energy	7/12/07		49,900,000	$	37,653	$	72,579
Petro Rubiales Energy-Warrants	7/12/07		17,212,500		4,910		9,496
				$	42,563	$	82,075

(d)  Security exempt from registration under Section 4(2) of the Securities Act of 1933. These securities may only be resold in exempt transactions to qualified buyers. Private resales of these securities to qualified institutional buyers are also exempt from registration pursuant to Rule 144A under the Securities Act of 1933. At December 31, 2007, these securities had an aggregate value of $75,796, which represented 2.5% of net assets.

(e)  At December 31, 2007, for federal income tax purposes cost of investments was $2,357,720 and net unrealized appreciation was $723,439 consisting of gross unrealized appreciation of $1,021,303 and gross unrealized depreciation of $297,864.

See accompanying notes to financial statements.

56

Columbia Thermostat Fund

Statement of Investments, December 31, 2007

Number of Shares or Principal Amount (000)			Value (000)
		> Bond Funds: 64.9%
	6,788,152	Columbia Intermediate Bond Fund, Class Z	$	59,600
	3,274,079	Columbia U.S. Treasury Index Fund, Class Z		35,720
	2,948,910	Columbia Conservative High Yield Fund, Class Z		23,798
Total Bond Funds (Cost: $119,036)				119,118
		> Stock Funds: 34.6%
	1,112,902	Columbia Large Cap Enhanced Core Fund, Class Z		15,859
	865,633	Columbia Dividend Income Fund, Class Z		12,690
	218,964	Columbia Acorn International, Class Z		9,547
	321,754	Columbia Acorn Fund, Class Z		9,527
	408,455	Columbia Marsico Growth Fund, Class Z		9,517
	224,606	Columbia Acorn Select, Class Z		6,381
Total Stock Funds (Cost: $57,066)				63,521
Short-Term Obligation: 0.9%
$	1,608	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by a U.S. Government Agency Obligation, maturing 8/20/12, market value $1,641 (repurchase proceeds $1,608)		1,608
		(Cost: $1,608)		1,608
Total Investments: 100.4% (Cost: $177,710)(a)				184,247
Cash and Other Assets Less Liabilities: (0.4)%				(719	)
Total Net Assets: 100%			$	183,528

> Notes to Statement of Investments (dollar values in thousands)

(a)  At December 31, 2007, for federal income tax purposes cost of investments was $178,495 and net unrealized appreciation was $5,752, consisting of gross unrealized appreciation of $7,296 and gross unrealized depreciation of $1,544.

See accompanying notes to financial statements.

57

Columbia Acorn Family of Funds

Statements of Assets and Liabilities

December 31, 2007	Columbia Acorn Fund			Columbia Acorn International			Columbia Acorn USA			Columbia Acorn International Select			Columbia Acorn Select			Columbia Thermostat Fund
(in thousands)
Assets:
Unaffiliated investments, at cost	$	9,458,367		$	3,887,622		$	1,236,713		$	210,736		$	1,526,940		$	1,608
Affiliated investments, at cost (See Note 4)		3,677,369			89,822			5,636			—			820,725			176,102
Unaffiliated investments, at value	$	14,902,114		$	5,753,160		$	1,579,696		$	265,609		$	2,345,478		$	1,608
Affiliated investments, at value (See Note 4)		5,035,542			77,254			4,622			—			735,681			182,639
Cash		—	*		167			123			—	*		748			—	*
Foreign currency (cost: Columbia Acorn Fund $2,383; Columbia Acorn International $8,509; Columbia Acorn International Select $12,598; Columbia Acorn Select $1)		2,407			8,515			—			12,808			1			—
Receivable for:
Investments sold		27,446			9,535			18,538			15			504			—
Fund shares sold		36,632			16,576			809			829			15,277			450
Dividends and interest		9,053			6,478			479			207			502			—	*
Foreign tax reclaims		185			340			—			24			—			—
Trustees' Deferred Compensation Investments		2,966			808			222			—			219			—
Total Assets		20,016,345			5,872,833			1,604,489			279,492			3,098,410			184,697
Liabilities:
Expense reimbursement due to Investment Adviser		—			—			—			—			—			3
Payable for:
Investments purchased		41,848			9,053			3,894			1,793			4,168			672
Fund shares redeemed		31,272			58,644			34,629			251			5,398			275
Management fee		10,955			3,781			1,185			218			2,084			15
Administration fee		648			188			52			9			100			6
12b-1 Service & Distribution fees		2,875			326			134			28			538			77
Reports to shareholders		814			234			92			22			199			40
Deferred Trustees' fees		2,966			808			222			30			219			24
Transfer agent fees		3,183			386			293			23			476			38
Trustees' fees		—	*		—	*		—	*		1			—	*		1
Audit fee		50			51			28			29			28			17
Custody fees		233			470			5			21			18			—
Chief compliance officer expenses		24			7			2			—	*		4			—	*
Deferred foreign capital gains tax payable		—			521			—			—			—			—
Other liabilities		131			36			11			50			19			1
Total Liabilities		94,999			74,505			40,547			2,475			13,251			1,169
Net Assets	$	19,921,346		$	5,798,328		$	1,563,942		$	277,017		$	3,085,159		$	183,528
Composition of Net Assets:
Paid in capital	$	12,765,066		$	3,854,515		$	1,170,442		$	216,960		$	2,287,904		$	176,414
Undistributed (overdistributed) net investment income (Accumulated net investment loss)		(7,414	)		9,909			(222	)		163			(10,038	)		167
Accumulated net realized gain		361,714			81,387			51,753			4,807			73,799			410
Net unrealized appreciation on:
Investments		6,801,920			1,852,970			341,969			54,873			733,494			6,537
Foreign capital gains tax		—			(521	)		—			—			—			—
Foreign currency translations		60			68			—			214			—	*		—
Net Assets	$	19,921,346		$	5,798,328		$	1,563,942		$	277,017		$	3,085,159		$	183,528
Net asset value per share – Class A (a)	$	28.87		$	43.42		$	27.23		$	31.74		$	27.89		$	12.31
(Net assets/shares)		($4,300,920/148,979)			($622,901/14,345)			($245,085/9,000)			($48,538/1,529)			($1,117,941/40,081)			($53,246/4,325)
Maximum offering price per share – Class A (b)	$	30.63		$	46.07		$	28.89		$	33.68		$	29.59		$	13.06
(Net asset value per share/front- end sales charge)		($28.87/0.9425)			($43.42/0.9425)			($27.23/0.9425)			($31.74/0.9425)			($27.89/0.9425)			($12.31/0.9425)
Net asset value and offering price per share – Class B (a)	$	27.39		$	42.46		$	25.87		$	30.50		$	26.57		$	12.38
(Net assets/shares)		($1,270,292/46,378)			($103,631/2,441)			($53,820/2,080)			($11,941/392)			($199,182/7,496)			($67,709/5,471)
Net asset value and offering price per share – Class C (a)	$	27.25		$	42.32		$	25.77		$	30.42		$	26.46		$	12.37
(Net assets/shares)		($1,312,243/48,162)			($153,416/3,625)			($50,743/1,969)			($13,023/428)			($197,100/7,449)			($26,908/2,175)
Net asset value and offering price per share – Class Z (c)	$	29.61		$	43.60		$	27.97		$	32.02		$	28.41		$	12.26
(Net assets/shares)		($13,037,891/440,350)			($4,918,380/112,805)			($1,214,294/43,419)			($203,515/6,356)			($1,570,936/55,302)			($35,665/2,910)

(a)  Redemption price per share is equal to net asset value less any applicable contingent deferred sales charge and redemption fee.

(b)  On sales of $50,000 or more the offering price is reduced.

(c)  Redemption price per share is equal to net asset value less any applicable redemption fee.

*  Rounds to less than $500.

See accompanying notes to financial statements.

58

Columbia Acorn Family of Funds

Statements of Operations
For the Year Ended December 31, 2007

(in thousands)	Columbia Acorn Fund			Columbia Acorn International			Columbia Acorn USA			Columbia Acorn International Select			Columbia Acorn Select			Columbia Thermostat Fund
Investment Income:
Dividend income	$	145,080		$	87,367		$	12,363		$	3,081		$	9,206		$	—
Dividend income from affiliates (See Note 4)		36,575			2,142			—			—			—			—
Dividends from affiliated investment company shares (See Note 4)		—			—			—			—			—			7,789
Interest income		56,916			17,028			3,194			586			11,149			40
		238,571			106,537			15,557			3,667			20,355			7,829
Foreign taxes withheld		(2,862	)		(6,403	)		—	*		(174	)		(65	)		—
Total Investment Income		235,709			100,134			15,557			3,493			20,290			7,829
Expenses:
Management fee		130,904			40,665			14,381			2,123			23,344			184
Administration fee		7,739			2,012			632			85			1,110			70
12b-1 Service and Distribution fees:
Class A		11,075			1,205			660			90			2,838			134
Class B		10,443			765			461			82			1,648			524
Class C		13,968			1,329			556			99			2,045			266
Transfer agent fees:
Class A		3,186			492			178			38			871			78
Class B		1,990			183			102			24			378			111
Class C		1,311			153			55			15			228			42
Class Z		4,387			1,267			573			75			565			39
Custody fees		1,588			2,881			48			104			128			—
Trustees' fees		822			218			69			24			242			24
Registration & blue sky fees		202			144			81			63			107			56
Reports to shareholders		1,932			620			287			96			529			125
Chief compliance officer expenses (See Note 4)		468			123			45			12			70			12
Other expenses		914			307			113			67			165			45
Total expenses		190,929			52,364			18,241			2,997			34,268			1,710
Less custody fees paid indirectly		(202	)		(2	)		(20	)		—	*		(53	)		—	*
Less reimbursement of expenses by Investment Adviser		—			—			—			—			—			(315	)
Less reimbursement of expenses by Transfer Agent
Class A		(222	)		(16	)		(12	)		(1	)		(54	)		(4	)
Class B		(86	)		(7	)		(4	)		(1	)		(16	)		(5	)
Class C		(63	)		(6	)		(2	)		(1	)		(9	)		(2	)
Class Z		(378	)		(26	)		(49	)		(1	)		(22	)		—	*
Net Expenses		189,978			52,307			18,154			2,993			34,114			1,384
Net Investment Income (Loss)		45,731			47,827			(2,597	)		500			(13,824	)		6,445
Net Realized and Unrealized Gain (Loss) on Portfolio Positions:
Net realized gain (loss) on:
Unaffiliated investments		1,424,022			508,011			134,988			28,059			131,210			—
Affiliated investments (See Note 4)		289,100			6,231			—			—			6,322			6,855
Foreign currency transactions		(1,028	)		(572	)		—			663			(204	)		—
Distributions from affiliated investment company shares		—			—			—			—			—			2,080
Realized loss due to a trading error		(4	)		—			—			—			—			—
Reimbursement of trading loss by Investment Advisor (See Note 8)		4			—			—			—			—			—
Net realized gain		1,712,094			513,670			134,988			28,722			137,328			8,935
Net change in net unrealized appreciation (depreciation) on:
Unaffiliated investments		(363,205	)		241,230			(78,501	)		12,803			228,164			—
Affiliated investments (See Note 4)		27,347			(8,791	)		(86	)		—			(167,579	)		(1,323	)
Foreign currency translations		38			17			—			211			69			—
Foreign capital gains tax		—			(521	)		—			—			—			—
Unrealized loss due to a trading error		—			—			(5	)		—			—			—
Reimbursement of trading loss by Investment Advisor (See Note 8)		—			—			5			—			—			—
Net change in unrealized appreciation (depreciation)		(335,820	)		231,935			(78,587	)		13,014			60,654			(1,323	)
Net realized and unrealized gain		1,376,274			745,605			56,401			41,736			197,982			7,612
Net Increase in Net Assets resulting from Operations	$	1,422,005		$	793,432		$	53,804		$	42,236		$	184,158		$	14,057

*  Rounds to less than $500.

See accompanying notes to financial statements.

59

Columbia Acorn Family of Funds

Statements of Changes in Net Assets

	Columbia Acorn Fund						Columbia Acorn International						Columbia Acorn USA
Increase (Decrease) in Net Assets	Year ended December 31,						Year ended December 31,						Year ended December 31,
(in thousands)	2007			2006			2007			2006			2007			2006
Operations:
Net investment income (loss)	$	45,731		$	35,190		$	47,827		$	31,386		$	(2,597	)	$	(3,110	)
Net realized gain on investments and foreign currency transactions		1,712,094			1,611,966			513,670			392,116			134,988			46,861
Net realized gain on affiliated investment company shares and distributions from affiliated investment company shares		—			—			—			—			—			—
Net change in net unrealized appreciation (depreciation) on investments and foreign currency translations		(335,820	)		712,218			231,935			645,701			(78,587	)		64,360
Net change in net unrealized appreciation (depreciation) on affiliated investment company shares		—			—			—			—			—			—
Net Increase from Operations		1,422,005			2,359,374			793,432			1,069,203			53,804			108,111
Distribution to Shareholders From:
Net investment income – Class A		(3,413	)		(5,394	)		(1,116	)		(2,223	)		—			—
Net realized gain – Class A		(325,538	)		(313,513	)		(43,244	)		(26,545	)		(15,400	)		(5,181	)
Net investment income – Class B		—			—			—	*		(141	)		—			—
Net realized gain – Class B		(102,379	)		(114,707	)		(7,707	)		(8,646	)		(3,468	)		(1,487	)
Net investment income – Class C		—			—			(2	)		(63	)		—			—
Net realized gain – Class C		(105,787	)		(109,093	)		(11,335	)		(8,998	)		(3,257	)		(1,223	)
Net investment income – Class Z		(48,153	)		(48,532	)		(35,860	)		(44,617	)		—			—
Net realized gain – Class Z		(960,719	)		(916,129	)		(359,596	)		(342,510	)		(72,632	)		(25,202	)
Total Distribution to Shareholders		(1,545,989	)		(1,507,368	)		(458,860	)		(433,743	)		(94,757	)		(33,093	)
Share Transactions:
Subscriptions – Class A		1,059,415			1,078,213			364,862			176,101			90,692			113,090
Distributions reinvested – Class A		298,039			288,002			40,913			25,843			13,230			4,383
Redemptions – Class A		(1,097,778	)		(822,590	)		(115,689	)		(63,857	)		(96,876	)		(51,382	)
Net Increase (Decrease) – Class A		259,676			543,625			290,086			138,087			7,046			66,091
Subscriptions – Class B		14,689			25,556			17,916			17,920			496			1,247
Distributions reinvested – Class B		93,667			104,566			7,027			8,016			3,174			1,351
Redemptions – Class B		(235,941	)		(212,371	)		(22,565	)		(20,296	)		(13,338	)		(14,036	)
Net Increase (Decrease) – Class B		(127,585	)		(82,249	)		2,378			5,640			(9,668	)		(11,438	)
Subscriptions – Class C		110,348			166,508			60,335			50,734			3,126			17,895
Distributions reinvested – Class C		83,502			86,726			8,403			6,707			2,798			1,038
Redemptions – Class C		(210,477	)		(178,699	)		(21,288	)		(16,582	)		(8,675	)		(8,640	)
Net Increase (Decrease) – Class C		(16,627	)		74,535			47,450			40,859			(2,751	)		10,293
Subscriptions – Class Z		1,935,968			1,754,910			996,581			707,961			236,636			371,430
Distributions reinvested – Class Z		863,071			824,254			279,036			279,893			65,865			22,838
Redemptions – Class Z		(1,814,299	)		(1,413,279	)		(495,473	)		(357,229	)		(272,461	)		(175,498	)
Net Increase – Class Z		984,740			1,165,885			780,144			630,625			30,040			218,770
Net Increase (Decrease) from Share Transactions		1,100,204			1,701,796			1,120,058			815,211			24,667			283,716
Redemption Fees		—			—			303			147			—			—
Total Increase (Decrease) in Net Assets		976,220			2,553,802			1,454,933			1,450,818			(16,286	)		358,734
Net Assets:
Beginning of period		18,945,126			16,391,324			4,343,395			2,892,577			1,580,228			1,221,494
End of period	$	19,921,346		$	18,945,126		$	5,798,328		$	4,343,395		$	1,563,942		$	1,580,228
Undistributed (Overdistributed) Net Investment Income or (Accumulated Net Investment Loss)	$	(7,414	)	$	(27,265	)	$	9,909		$	(20,256	)	$	(222	)	$	(174	)

*  Rounds to less than $500.

See accompanying notes to financial statements.

60

	Columbia Acorn International Select						Columbia Acorn Select						Columbia Thermostat Fund
Increase (Decrease) in Net Assets	Year ended December 31,						Year ended December 31,						Year ended December 31,
(in thousands)	2007			2006			2007			2006			2007			2006
Operations:
Net investment income (loss)	$	500		$	361		$	(13,824	)	$	(11,032	)	$	6,445		$	6,358
Net realized gain on investments and foreign currency transactions		28,722			18,110			137,328			71,803			—			—
Net realized gain on affiliated investment company shares and distributions from affiliated investment company shares		—			—			—			—			8,935			11,669
Net change in net unrealized appreciation (depreciation) on investments and foreign currency translations		13,014			20,770			60,654			287,875			—			—
Net change in net unrealized appreciation (depreciation) on affiliated investment company shares		—			—			—			—			(1,323	)		836
Net Increase from Operations		42,236			39,241			184,158			348,646			14,057			18,863
Distribution to Shareholders From:
Net investment income – Class A		(150	)		(2	)		—			(788	)		(2,012	)		(2,086	)
Net realized gain – Class A		(2,498	)		—			(25,546	)		(20,503	)		(3,166	)		(3,300	)
Net investment income – Class B		—			—			—			—			(2,100	)		(2,114	)
Net realized gain – Class B		(655	)		—			(4,903	)		(4,991	)		(4,129	)		(3,980	)
Net investment income – Class C		—			—	*		—			—			(764	)		(753	)
Net realized gain – Class C		(682	)		—			(4,795	)		(3,972	)		(1,608	)		(1,496	)
Net investment income – Class Z		(1,618	)		(196	)		—			(1,614	)		(1,519	)		(1,223	)
Net realized gain – Class Z		(10,710	)		—			(33,588	)		(19,241	)		(2,094	)		(1,585	)
Total Distribution to Shareholders		(16,313	)		(198	)		(68,832	)		(51,109	)		(17,392	)		(16,537	)
Share Transactions:
Subscriptions – Class A		26,720			10,850			353,434			210,532			10,451			6,298
Distributions reinvested – Class A		2,409			2			23,371			19,667			4,734			4,887
Redemptions – Class A		(7,228	)		(3,070	)		(257,380	)		(158,467	)		(19,044	)		(25,185	)
Net Increase (Decrease) – Class A		21,901			7,782			119,425			71,732			(3,859	)		(14,000	)
Subscriptions – Class B		2,760			2,223			3,529			4,782			4,269			3,578
Distributions reinvested – Class B		583			—			4,372			4,452			5,698			5,496
Redemptions – Class B		(2,545	)		(1,437	)		(36,416	)		(31,688	)		(13,592	)		(16,105	)
Net Increase (Decrease) – Class B		798			786			(28,515	)		(22,454	)		(3,625	)		(7,031	)
Subscriptions – Class C		5,815			2,333			44,306			20,817			4,372			4,114
Distributions reinvested – Class C		579			—	*		3,773			3,230			2,127			1,960
Redemptions – Class C		(1,469	)		(924	)		(32,811	)		(22,947	)		(6,502	)		(7,323	)
Net Increase (Decrease) – Class C		4,925			1,409			15,268			1,100			(3	)		(1,249	)
Subscriptions – Class Z		70,464			34,878			874,944			258,516			6,608			5,698
Distributions reinvested – Class Z		5,636			99			25,110			14,293			3,354			2,633
Redemptions – Class Z		(21,559	)		(10,107	)		(274,110	)		(170,328	)		(4,141	)		(3,204	)
Net Increase – Class Z		54,541			24,870			625,944			102,481			5,821			5,127
Net Increase (Decrease) from Share Transactions		82,165			34,847			732,122			152,859			(1,666	)		(17,153	)
Redemption Fees		31			9			—			—			—			—
Total Increase (Decrease) in Net Assets		108,119			73,899			847,448			450,396			(5,001	)		(14,827	)
Net Assets:
Beginning of period		168,898			94,999			2,237,711			1,787,315			188,529			203,356
End of period	$	277,017		$	168,898		$	3,085,159		$	2,237,711		$	183,528		$	188,529
Undistributed (Overdistributed) Net Investment Income or (Accumulated Net Investment Loss)	$	163		$	676		$	(10,038	)	$	(9,971	)	$	167		$	249

61

Columbia Acorn Family of Funds

Statements of Changes in Net Assets, continued

	Columbia Acorn Fund						Columbia Acorn International						Columbia Acorn USA
Changes in Shares of Beneficial Interest:	Year ended December 31,						Year ended December 31,						Year ended December 31,
(in thousands)	2007			2006			2007			2006			2007			2006
Subscriptions – Class A		34,304			37,015			8,200			4,588			3,109			4,113
Shares issued in reinvestment and capital gains – Class A		10,082			9,911			931			673			475			156
Less shares redeemed – Class A		(35,563	)		(28,264	)		(2,608	)		(1,723	)		(3,347	)		(1,877	)
Net Increase (Decrease) – Class A		8,823			18,662			6,523			3,538			237			2,392
Subscriptions – Class B		501			909			410			482			18			47
Shares issued in reinvestment and capital gains – Class B		3,332			3,757			164			212			119			50
Less shares redeemed – Class B		(7,999	)		(7,576	)		(523	)		(553	)		(478	)		(533	)
Net Increase (Decrease) – Class B		(4,166	)		(2,910	)		51			141			(341	)		(436	)
Subscriptions – Class C		3,792			5,931			1,389			1,356			113			678
Shares issued in reinvestment and capital gains – Class C		2,987			3,123			196			178			105			39
Less shares redeemed – Class C		(7,188	)		(6,396	)		(487	)		(455	)		(312	)		(328	)
Net Increase (Decrease) – Class C		(409	)		2,658			1,098			1,079			(94	)		389
Subscriptions – Class Z		61,171			58,774			22,406			18,601			7,861			13,228
Shares issued in reinvestment and capital gains – Class Z		28,499			27,709			6,321			7,251			2,304			796
Less shares redeemed – Class Z		(57,473	)		(47,499	)		(11,085	)		(9,331	)		(9,118	)		(6,302	)
Net Increase – Class Z		32,197			38,984			17,642			16,521			1,047			7,722
Net Increase (Decrease) in Shares of Beneficial Interest		36,445			57,394			25,314			21,279			849			10,067

*  Rounds to less than 500 shares.

See accompanying notes to financial statements.

62

	Columbia Acorn International Select						Columbia Acorn Select						Columbia Thermostat Fund
Changes in Shares of Beneficial Interest:	Year ended December 31,						Year ended December 31,						Year ended December 31,
(in thousands)	2007			2006			2007			2006			2007			2006
Subscriptions – Class A		867			446			12,257			8,645			805			492
Shares issued in reinvestment and capital gains – Class A		75			—	*		810			777			380			390
Less shares redeemed – Class A		(230	)		(131	)		(8,919	)		(6,607	)		(1,469	)		(1,960	)
Net Increase (Decrease) – Class A		712			315			4,148			2,815			(284	)		(1,078	)
Subscriptions – Class B		93			97			129			207			328			279
Shares issued in reinvestment and capital gains – Class B		19			—	*		159			183			456			437
Less shares redeemed – Class B		(86	)		(64	)		(1,320	)		(1,373	)		(1,046	)		(1,253	)
Net Increase (Decrease) – Class B		26			33			(1,032	)		(983	)		(262	)		(537	)
Subscriptions – Class C		194			100			1,601			898			338			322
Shares issued in reinvestment and capital gains – Class C		19			—	*		138			133			170			156
Less shares redeemed – Class C		(49	)		(42	)		(1,197	)		(1,002	)		(502	)		(572	)
Net Increase (Decrease) – Class C		164			58			542			29			6			(94	)
Subscriptions – Class Z		2,248			1,448			29,644			10,565			511			442
Shares issued in reinvestment and capital gains – Class Z		176			5			858			559			271			210
Less shares redeemed – Class Z		(696	)		(427	)		(9,406	)		(7,111	)		(320	)		(248	)
Net Increase – Class Z		1,728			1,026			21,096			4,013			462			404
Net Increase (Decrease) in Shares of Beneficial Interest		2,630			1,432			24,754			5,874			(78	)		(1,305	)

63

Columbia Acorn Family of Funds

Financial Highlights

Columbia Acorn Fund

Class Z	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	29.71		$	28.17		$	26.45		$	22.56		$	15.50
Income from Investment Operations
Net investment income (a)		0.15	(b)		0.13			0.15			0.04			0.03
Net realized and unrealized gain		2.17			3.92			3.28			4.78			7.05
Total from Investment Operations		2.32			4.05			3.43			4.82			7.08
Less Distributions Declared to Shareholders
From net investment income		(0.12	)		(0.13	)		(0.15	)		(0.02	)		—
From net realized gains		(2.30	)		(2.38	)		(1.56	)		(0.91	)		(0.02	)
Total Distributions Declared to Shareholders		(2.42	)		(2.51	)		(1.71	)		(0.93	)		(0.02	)
Net Asset Value, End of Period	$	29.61		$	29.71		$	28.17		$	26.45		$	22.56
Total Return (c)		7.69	%(d)(e)		14.45	%(d)		13.11	%(d)		21.51	%(d)		45.68	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		0.74	%		0.74	%		0.74	%		0.81	%		0.80	%
Net investment income (f)		0.46	%		0.45	%		0.57	%		0.18	%		0.17	%
Waiver/reimbursement		0.00	%(g)		0.01	%		0.02	%		0.02	%		—
Portfolio turnover rate		20	%		22	%		16	%		20	%		10	%
Net assets at end of period (in millions)	$	13,038		$	12,128		$	10,399		$	8,689		$	7,065

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.03 per share.

(c)  Total return at net asset value assuming all distributions reinvested.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Total return includes a voluntary reimbursement by the Investment Adviser for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by less than 0.01% and less than $0.01, respectively.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g)  Rounds to less than 0.01%.

Columbia Acorn International

Class Z	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	40.31		$	33.44		$	29.03		$	22.66		$	15.40
Income from Investment Operations
Net investment income (a)		0.43			0.35			0.34			0.25			0.21
Net realized and unrealized gain		6.56			10.94			5.87			6.37			7.13
Total from Investment Operations		6.99			11.29			6.21			6.62			7.34
Less Distributions Declared to Shareholders
From net investment income		(0.34	)		(0.51	)		(0.72	)		(0.25	)		(0.08	)
From net realized gains		(3.36	)		(3.91	)		(1.08	)		—			—
Total Distributions Declared to Shareholders		(3.70	)		(4.42	)		(1.80	)		(0.25	)		(0.08	)
Redemption Fees
Redemption fees added to paid in capital		0.00	(a)(b)		0.00	(a)(b)		0.00	(a)(b)		0.00	(a)(b)		—
Net Asset Value, End of Period	$	43.60		$	40.31		$	33.44		$	29.03		$	22.66
Total Return (c)		17.28	%(d)		34.53	%(d)		21.81	%(d)		29.47	%(d)		47.80	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (e)		0.91	%		0.94	%		0.99	%		1.08	%		1.05	%
Net investment income (e)		0.96	%		0.92	%		1.09	%		1.01	%		1.19	%
Waiver/reimbursement		0.00	%(f)		0.01	%		0.02	%		0.02	%		—
Portfolio turnover rate		28	%		31	%		27	%		40	%		40	%
Net assets at end of period (in millions)	$	4,918		$	3,836		$	2,629		$	1,919		$	1,563

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Rounds to less than $0.01 per share.

(c)  Total return at net asset value assuming all distributions reinvested.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(f)  Rounds to less than 0.01%.

Columbia Acorn USA

Class Z	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	28.66		$	27.03		$	25.20		$	21.01		$	14.28
Income from Investment Operations
Net investment income (loss) (a)		(0.01	)(b)		(0.02	)		0.07			(0.15	)		(0.13	)
Net realized and unrealized gain		1.03			2.26			3.18			4.48			6.86
Total from Investment Operations		1.02			2.24			3.25			4.33			6.73
Less Distributions Declared to Shareholders
From net investment income		—			—			(0.05	)		—			—
From net realized gains		(1.71	)		(0.61	)		(1.37	)		(0.14	)		—
Total Distributions Declared to Shareholders		(1.71	)		(0.61	)		(1.42	)		(0.14	)		—
Net Asset Value, End of Period	$	27.97		$	28.66		$	27.03		$	25.20		$	21.01
Total Return (c)		3.46	%(d)(e)		8.28	%(d)		12.98	%(d)		20.62	%(d)		47.13	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		0.98	%		0.98	%		1.01	%		1.09	%		1.11	%
Net investment income (loss) (f)		(0.03	)%		(0.07	)%		0.28	%		(0.66	)%		(0.72	)%
Waiver/reimbursement		0.00	%(g)		0.01	%		0.01	%		0.02	%		—
Portfolio turnover rate		21	%		13	%		13	%		18	%		7	%
Net assets at end of period (in millions)	$	1,214		$	1,214		$	937		$	646		$	502

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.09 per share.

(c)  Total return at net asset value assuming all distributions reinvested.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Total return includes a voluntary reimbursement by the Investment Adviser for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by less than 0.01% and less than $0.01, respectively.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g)  Rounds to less than 0.01%.

See accompanying notes to financial statements.

64

Columbia Acorn International Select

Class Z	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	27.97		$	20.57		$	18.02		$	14.58		$	10.29
Income from Investment Operations
Net investment income (a)		0.14	(b)		0.10			0.13			0.04			0.06
Net realized and unrealized gain		5.96			7.35			2.70			3.47			4.24
Total from Investment Operations		6.10			7.45			2.83			3.51			4.30
Less Distributions Declared to Shareholders
From net investment income		(0.28	)		(0.05	)		(0.28	)		(0.07	)		(0.01	)
From net realized gains		(1.77	)		—			—			—			—
Total Distributions Declared to Shareholders		(2.05	)		(0.05	)		(0.28	)		(0.07	)		(0.01	)
Redemption Fees
Redemption fees added to paid in capital		0.00	(a)(c)		0.00	(a)(c)		0.00	(a)(c)		0.00	(a)(c)		—
Net Asset Value, End of Period	$	32.02		$	27.97		$	20.57		$	18.02		$	14.58
Total Return (d)(e)		21.86	%		36.27	%		15.98	%		24.14	%		41.79	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.18	%		1.27	%		1.45	%		1.45	%		1.45	%
Net investment income (f)		0.44	%		0.44	%		0.72	%		0.27	%		0.56	%
Waiver/reimbursement		0.00	%(g)		0.01	%		0.04	%		0.29	%		0.42	%
Portfolio turnover rate		57	%		47	%		39	%		73	%		69	%
Net assets at end of period (in millions)	$	204		$	129		$	74		$	46		$	34

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.07 per share.

(c)  Rounds to less than $0.01 per share.

(d)  Total return at net asset value assuming all distributions reinvested.

(e)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g)  Rounds to less than 0.01%.

Columbia Acorn Select

Class Z	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	26.59		$	22.77		$	21.13		$	18.20		$	14.04
Income from Investment Operations
Net investment loss (a)		(0.07	)		(0.06	)		(0.03	)		(0.10	)		(0.10	)
Net realized and unrealized gain		2.53			4.51			2.35			3.47			4.39
Total from Investment Operations		2.46			4.45			2.32			3.37			4.29
Less Distributions Declared to Shareholders
From net investment income		—			(0.04	)		—			—			—
From net realized gains		(0.64	)		(0.59	)		(0.68	)		(0.44	)		(0.13	)
Total Distributions Declared to Shareholders		(0.64	)		(0.63	)		(0.68	)		(0.44	)		(0.13	)
Net Asset Value, End of Period	$	28.41		$	26.59		$	22.77		$	21.13		$	18.20
Total Return (b)		9.20	%(c)		19.68	%(c)		11.08	%(c)		18.58	%(c)		30.61	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (d)		0.91	%		0.96	%		0.99	%		1.13	%		1.12	%
Net investment loss (d)		(0.24	)%		(0.26	)%		(0.16	)%		(0.52	)%		(0.63	)%
Waiver/reimbursement		0.00	%(e)		0.02	%		0.03	%		0.02	%		—
Portfolio turnover rate		14	%		21	%		19	%		34	%		16	%
Net assets at end of period (in millions)	$	1,571		$	909		$	688		$	445		$	294

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Total return at net asset value assuming all distributions reinvested.

(c)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(d)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(e)  Rounds to less than 0.01%.

Columbia Thermostat Fund

Class Z	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	12.57		$	12.50			13.12		$	12.31		$	10.41
Income from Investment Operations
Net investment income (a)		0.52			0.49			0.43			0.31			0.19
Net realized and unrealized gain		0.53			0.84			0.28			0.82			1.87
Total from Investment Operations		1.05			1.33			0.71			1.13			2.06
Less Distributions Declared to Shareholders
From net investment income		(0.57	)		(0.54	)		(0.42	)		(0.29	)		(0.16	)
From net realized gains		(0.79	)		(0.72	)		(0.91	)		(0.03	)		(0.00	)(b)
Total Distributions Declared to Shareholders		(1.36	)		(1.26	)		(1.33	)		(0.32	)		(0.16	)
Net Asset Value, End of Period	$	12.26		$	12.57		$	12.50		$	13.12		$	12.31
Total Return (c)(d)		8.49	%		10.86	%		5.50	%		9.17	%		19.79	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (e)(f)		0.25	%		0.25	%		0.25	%		0.25	%		0.38	%
Net investment income (f)		4.05	%		3.84	%		3.28	%		2.48	%		1.64	%
Waiver/reimbursement		0.15	%		0.13	%		0.11	%		0.21	%		0.88	%
Portfolio turnover rate		128	%		66	%		96	%		67	%		61	%
Net assets at end of period (in millions)	$	36		$	31		$	26		$	21		$	14

(a)  Per share data was calculated using the average shares outstanding during the period. Recognition of net investment income by the Fund is affected by the timing of the declaration of dividends by the underlying investment companies in which the Fund invests.

(b)  Rounds to less than $0.01 per share.

(c)  Total return at net asset value assuming all distributions reinvested.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Does not include expenses of the investment companies in which the Fund invests.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

See accompanying notes to financial statements.

65

Columbia Acorn Family of Funds

Notes to Financial Statements

1.  Nature of Operations

Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select and Columbia Thermostat Fund (the "Funds") are each a series of Columbia Acorn Trust (the "Trust"), an open-end management investment company organized as a Massachusetts business trust. The investment objective of each Fund, excluding Columbia Thermostat Fund, is to seek long-term growth of capital. The investment objective of Columbia Thermostat Fund is to provide long-term total return. Columbia Thermostat Fund pursues its investment objective by investing in shares of other mutual funds. As a "fund of funds," under normal circumstances, the Fund allocates at least 95% of its net assets among a selected group of stock and bond mutual funds ("portfolio funds") according to the current level of the Standard & Poor's 500 Stock Index in relation to predetermined ranges set by the Fund's investment adviser. The Fund may invest up to 5% of its net assets plus any cash received that day in cash, repurchase agreements, high quality short-term paper and government securities.

The Funds may issue an unlimited number of shares. The Funds currently offer four classes of shares: Class A, Class B, Class C and Class Z. Effective February 29, 2008, the Funds will no longer offer Class B shares.

Class A shares are sold with a front-end sales charge. Class A shares bought without an initial sales charge in accounts aggregating $1 million to $50 million at the time of purchase are subject to a 1.00% contingent deferred sales charge ("CDSC") if the shares are sold within 12 months of the date of purchase.

Class B shares are subject to a CDSC if sold within six years of purchase. Class B shares will convert to Class A shares automatically eight years after purchase.

Class C shares are subject to a CDSC on redemptions made within one year after purchase.

Class Z shares are offered continuously at net asset value. There are certain restrictions on the purchase of Class Z shares. Generally, Class Z shares of a Fund may be exchanged for shares of another fund distributed by Columbia Management Distributors, Inc. at no additional charge.

Columbia Acorn International and Columbia Acorn International Select impose a 2% redemption fee on Class A, Class B, Class C and Class Z shares that are redeemed within 60 days or less of purchase. See the discussion of Fund policies regarding the trading of Fund shares as disclosed in the Funds' prospectuses for more information.

The financial highlights for Class A, Class B and Class C shares are presented in a separate annual report.

Investment income, realized and unrealized gains and losses, and certain fund-level expenses are allocated pro rata on the basis of the relative net assets of all classes, except each class bears certain expenses unique to that class such as distribution services, transfer agency, and certain other class specific expenses. Differences in class expenses may result in payment of different dividend distributions for each class. All the Funds' share classes have equal rights with respect to voting subject to Fund or class specific matters.

2.  Significant Accounting Policies

>Security valuation

Securities of the Funds are valued at market value or, if a market quotation for a security is not readily available or is deemed not to be reliable because of events or circumstances that have occurred between the market quotation and the time as of which the security is to be valued, the security is valued at a fair value determined in accordance with procedures established by the Board of Trustees. With respect to Columbia Thermostat Fund, investments in portfolio funds are valued at their net asset value as reported by the portfolio funds. A security traded on a securities exchange or in over-the-counter market in which transaction prices are reported is valued at the last sales price at the time of valuation. A security traded principally on NASDAQ is valued at the NASDAQ official closing price. A security for which there is no reported sale on the valuation date is valued at the latest bid quotation. A short-term debt obli gation having a maturity of 60 days or less from the valuation date is valued at amortized cost, which approximates fair value. A security for which a market quotation is not readily available and any other assets are fair valued in accordance with procedures established by the Board of Trustees. The Funds have retained an independent statistical fair value pricing service to assist in the fair valuation process for securities principally traded in a foreign market in order to adjust for possible changes in value that may occur between the close of the foreign exchange and the time as of which the securities are to be valued. If a security is valued at fair value, that value may be different from the last quoted market price for the security.

In September 2006, Statement of Financial Accounting Standards No. 157, Fair Value Measurements ("SFAS 157"), was issued. SFAS 157 is effective for fiscal years beginning after November 15, 2007. SFAS 157 defines fair value, establishes a framework for measuring fair value and expands disclosures

66

about fair value measurements. Management is evaluating the impact the application of SFAS 157 will have on the Funds' financial statement disclosures.

>Repurchase agreements

The Funds may engage in repurchase agreement transactions. The Funds, through their custodians, receive delivery of underlying securities collateralizing repurchase agreements. The custodian determines that the value of the underlying securities is at all times at least equal to the resale price. In the event of default or bankruptcy by the other party to the agreement, realization and/or retention of the collateral may be subject to legal proceedings.

>Foreign currency translations

Values of investments denominated in foreign currencies are converted into U.S. dollars using the spot market rate of exchange at the time of valuation. Purchases and sales of investments and dividend and interest income are translated into U.S. dollars using the spot market rate of exchange prevailing on the respective dates of such transactions. The gain or loss resulting from changes in foreign exchange rates is included with net realized and unrealized gain or loss from investments, as appropriate.

>Security transactions and investment income

Security transactions, investment income and shareholder fund transactions are accounted for on the trade date (date the order to buy or sell is executed) and dividend income and realized gain distributions from other funds are recorded on the ex-dividend date, except that certain dividends from foreign securities are recorded as soon as the information is available to the Funds. Interest income is recorded on the accrual basis and includes amortization of discounts on debt obligations when required for federal income tax purposes. Realized gains and losses from security transactions are recorded on an identified cost basis.

Awards, if any, from class action litigation related to securities owned may be recorded as a reduction of cost of those securities. If the applicable securities are no longer owned, the proceeds are recorded as realized gains.

The Funds estimate the tax character of distributions from real estate investment trusts ("REITs"). Distributions received in excess of income are recorded as a reduction of the cost of the related investments. If the applicable securities are no longer owned, any distributions received in excess of income are recorded as realized gains.

>Restricted Securities

Restricted securities are securities that may only be resold upon registration under federal securities laws or in transactions exempt from registration. In some cases, the issuer of restricted securities has agreed to register such securities for resale at the issuer's expense either upon demand by the Funds or in connection with another registered offering of the securities. Many restricted securities may be resold in the secondary market in transactions exempt from registration. Such restricted securities may be determined to be liquid under criteria established by the Board of Trustees. The Funds will not incur any registration costs upon such resale.

>Use of estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America ("GAAP") requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results may differ from those estimates.

>Fund share valuation

Fund shares are sold and redeemed on a continuing basis at net asset value subject to any applicable sales charge. Net asset value per share is determined daily as of the close of trading on the New York Stock Exchange ("NYSE") on each day the NYSE is open for trading. All income, expenses (other than the Class A, Class B and Class C shares Rule 12b-1 service and distribution fees and the Class A, Class B, Class C and Class Z shares transfer agency fees) and realized and unrealized gains (losses) of a Fund are allocated to each class proportionately on a daily basis for purposes of determining the net asset value of each class. Redemption fees are accounted for as an addition to paid in capital for purposes of determining the net asset value of each class.

>Custody fees/credits

Custody fees are reduced based on each Fund's cash balances maintained with the custodian. The amount is disclosed as a reduction of total expenses on the Statements of Operations.

>Federal income taxes

The Funds have complied with the provisions of the Internal Revenue Code available to regulated investment companies and, in the manner provided therein, distribute all their taxable income, as well as any net realized gain on sales of investments and foreign currency transactions reportable for federal income tax purposes. Columbia Thermostat Fund distributes all of its taxable income, as well as any net realized gain on

67

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

sales of portfolio fund shares and any distributions of net realized gains received by the Fund from its portfolio funds, reportable for federal income tax purposes. Accordingly, the Funds paid no federal income taxes and no federal income tax provision was required.

>Foreign capital gains taxes

Realized gains in certain countries may be subject to foreign taxes at the fund level, at rates ranging from approximately 10% to 15%. The Funds accrue for such foreign taxes on net realized and unrealized gains at the appropriate rate for each jurisdiction.

>Distributions to Shareholders

Distributions to shareholders are recorded on the ex-date.

>Indemnification

In the normal course of business, each Fund enters into contracts that contain a variety of representations and warranties and which provide general indemnities. A Fund's maximum exposure under these arrangements is unknown, as this would involve future claims against the Fund. Also, under the Trust's organizational documents, the Trustees and Officers of the Trust are indemnified against certain liabilities that may arise out of their duties to the Trust. However, based on experience, the Funds expect the risk of loss due to these warranties and indemnities to be minimal.

3.  Federal Tax Information

The timing and character of income and capital gain distributions are determined in accordance with income tax regulations, which may differ from GAAP. Reclassifications are made to the Funds' capital accounts for permanent tax differences to reflect income and gains available for distribution (or available capital loss carryforwards) under income tax regulations.

For the year ended December 31, 2007, permanent book and tax basis differences resulting primarily from differing treatments for distribution reclassifications, tax equalization, foreign currency transactions, passive foreign investment company ("PFIC") adjustments, foreign capital gains tax adjustments and REIT adjustments were identified and reclassified among the components of the Fund's net assets as follows:

	Undistributed/ (Overdistributed) Net Investment Income or (Accumulated Net Investment Loss)			Accumulated Net Realized Gain or (Net Realized Loss)			Paid-In Capital
(in thousands)
Columbia Acorn Fund	$	25,686		$	(106,021	)	$	80,335
Columbia Acorn International		19,316			(37,617	)		18,301
Columbia Acorn USA		2,549			(1,848	)		(701	)
Columbia Acorn International Select		755			(755	)		—
Columbia Acorn Select		13,757			(13,605	)		(152	)
Columbia Thermostat Fund		(132	)		(811	)		943

Net investment income and net realized gains (losses), as disclosed on the Statement of Operations, and net assets were not affected by this reclassification.

The tax character of distributions paid during the years ended December 31, 2007, and December 31, 2006, was as follows:

December 31, 2007	Ordinary Income*		Long-Term Capital Gains
(in thousands)
Columbia Acorn Fund	$	154,770	$	1,391,219
Columbia Acorn International		59,527		399,333
Columbia Acorn USA		—		94,757
Columbia Acorn International Select		1,768		14,545
Columbia Acorn Select		9,164		59,668
Columbia Thermostat Fund		12,086		5,306
December 31, 2006	Ordinary Income*		Long-Term Capital Gains
(in thousands)
Columbia Acorn Fund	$	102,167	$	1,405,201
Columbia Acorn International		47,043		386,698
Columbia Acorn USA		—		33,093
Columbia Acorn International Select		198		—
Columbia Acorn Select		9,493		41,617
Columbia Thermostat Fund		7,031		9,506

*For tax purposes short-term capital gains distributions, if any, are considered ordinary income distributions.

As of December 31, 2007, the components of distributable earnings on a tax basis were as follows:

	Undistributed Ordinary Income		Undistributed Long-term Capital Gains		Net Unrealized Appreciation (Depreciation)*
(in thousands)
Columbia Acorn Fund	$	21,930	$	341,600	$	6,795,790
Columbia Acorn International		20,343		74,297		1,850,478
Columbia Acorn USA		—		53,514		341,725
Columbia Acorn International Select		501		4,740		54,647
Columbia Acorn Select		—		74,034		723,439
Columbia Thermostat Fund		561		824		5,752

* The differences between book-basis and tax-basis net unrealized appreciation/depreciation are primarily due to deferral of losses from wash sales and PFIC adjustments.

Unrealized appreciation and depreciation at December 31, 2007, based on cost of investments for federal income tax purposes, were:

	Unrealized Appreciation		Unrealized Depreciation			Net Unrealized Appreciation
(in thousands)
Columbia Acorn Fund	$	7,838,307	$	(1,042,517	)	$	6,795,790
Columbia Acorn International		2,094,574		(244,096	)		1,850,478
Columbia Acorn USA		494,581		(152,856	)		341,725
Columbia Acorn International Select		65,182		(10,535	)		54,647
Columbia Acorn Select		1,021,303		(297,864	)		723,439
Columbia Thermostat Fund		7,296		(1,544	)		5,752

68

The following capital loss carryforwards may be available to reduce taxable income arising from future net realized gains on investments, if any, to the extent permitted by the Internal Revenue Code:

Year of Expiration		Columbia Acorn USA			Columbia Acorn International Select
(in thousands)
	2009	$	1,012	*	$	—
	2010		506	*		6,126
	2011		—			2,488
	TOTAL	$	1,518		$	8,614

*Of these carryforwards, $1,518 (expiring in 2009 and 2010) remains from Columbia Acorn USA's merger with Stein Roe Small Company Growth Fund on 7/26/2002. Utilization of Stein Roe Small Company Growth Fund's losses could be subject to limitations imposed by the Internal Revenue Code.

The following capital loss carryforwards were utilized during the year ended December 31, 2007:

(in thousands)
Columbia Acorn USA	$	506

The Funds adopted Financial Accounting Standards Board ("FASB") Interpretation No. 48, Accounting for Uncertainty in Income Taxes – an Interpretation of FASB Statement No. 109 ("FIN 48") effective June 29, 2007. FIN 48 requires management to determine whether a tax position of the Fund is more likely than not to be sustained upon examination by the applicable taxing authority, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The tax benefit to be recognized is measured as the largest amount of benefit that is greater than fifty percent likely of being realized upon ultimate settlement. FIN 48 must be applied to all existing tax positions upon initial adoption and the cumulative effect, if any, is to be reporte d as an adjustment to net assets. Management has evaluated the known implications of FIN 48 on its computation of net assets for the Funds. As a result of this evaluation, management believes that FIN 48 does not have any effect on the Fund's financial statements. However, management's conclusions regarding FIN 48 may be subject to review and adjustment at a later date based on factors including, but not limited to, further implementation guidance from the FASB, new tax laws, regulations, and administrative interpretations (including relevant court decisions). Each Fund's federal tax returns for the prior three fiscal years remain subject to examination by the Internal Revenue Service. The Funds are not aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months.

4.  Transactions with Affiliates

Columbia Wanger Asset Management, L.P. ("CWAM") is a wholly owned subsidiary of Columbia Management Group, LLC, which in turn is an indirect, wholly owned subsidiary of Bank of America Corporation ("BOA"). CWAM furnishes continuing investment supervision to the Funds and is responsible for the overall management of the Funds' business affairs.

Effective August 1, 2007, under the Funds' investment advisory agreement, fees are accrued daily based on the Funds' average daily net assets and paid monthly to CWAM at the annual rates shown in the table below for Columbia Acorn International Select:

Columbia Acorn International Select

Average Daily Net Assets		Annual Fee Rate
	Up to $500 million		0.94	%
	$500 million and over		0.90	%

For all of the other Funds, and also prior to August 1, 2007, for Columbia Acorn International Select, for the period covered by this report as provided under the Funds' investment advisory agreement, fees were accrued daily based on the Funds' average daily net assets and paid monthly to CWAM at the annual rates shown in the table below for each Fund.

Columbia Acorn Fund

Average Daily Net Assets	Annual Fee Rate
Up to $700 million		0.74	%
$700 million to $2 billion		0.69	%
$2 billion to $6 billion		0.64	%
$6 billion and over		0.63	%

Columbia Acorn International

Average Daily Net Assets	Annual Fee Rate
Up to $100 million		1.19	%
$100 million to $500 million		0.94	%
$500 million and over		0.74	%

Columbia Acorn USA

Average Daily Net Assets	Annual Fee Rate
Up to $200 million		0.94	%
$200 million to $500 million		0.89	%
$500 million to $2 billion		0.84	%
$2 billion to $3 billion		0.80	%
$3 billion and over		0.70	%

69

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

Columbia Acorn Select

Average Daily Net Assets	Annual Fee Rate
Up to $700 million		0.85	%
$700 million to $2 billion		0.80	%
$2 billion to $3 billion		0.75	%
$3 billion and over		0.70	%

Columbia Acorn International Select

All Average Daily Net Assets 0.94 %

Columbia Thermostat Fund

All Average Daily Net Assets 0.10 %

For the year ended December 31, 2007, the Funds' effective investment advisory fee rates were as follows:

Columbia Acorn Fund	0.64	%
Columbia Acorn International	0.76	%
Columbia Acorn USA	0.86	%
Columbia Acorn International Select	0.94	%
Columbia Acorn Select	0.79	%
Columbia Thermostat Fund	0.10	%

>Expense Limit

CWAM has voluntarily agreed to reimburse the ordinary operating expenses (exclusive of interest, taxes and extraordinary expenses, but inclusive of custodial charges relating to overdrafts, if any), after giving effect to any balance credits from the Funds' custodian, exceeding 1.45% annually of the average daily net assets for Columbia Acorn International Select's Class Z shares and 1.35% annually of the average daily net assets for Columbia Acorn Select's Class Z shares. This arrangement may be modified or terminated by either the Funds or CWAM on 30 days notice.

CWAM has contractually agreed to waive fees and/or reimburse expenses so that the ordinary operating expenses (exclusive of interest and fees on borrowings and expenses associated with the Fund's investment in other investment companies, but inclusive of custodial charges relating to overdrafts, if any), after giving effect to any balance credits from the Fund's custodian, will not exceed 0.25% annually of the average daily net assets of Columbia Thermostat Fund's Class Z shares through April 30, 2008. There is no guarantee that this arrangement will continue thereafter.

Expenses reimbursed by CWAM for Columbia Thermostat Fund for the year ended December 31, 2007, were $315,004.

CWAM provides administrative services and receives an administration fee from the Funds at the following annual rates:

Columbia Acorn Trust

Aggregate Average Daily Net Assets of the Trust:	Annual Fee Rate
Up to $8 billion		0.05	%
$8 billion to $16 billion		0.04	%
$16 billion and over		0.03	%

For the year ended December 31, 2007, each Fund's effective administration fee rate was 0.04% of average daily net assets. CWAM has delegated to Columbia Management Advisors, LLC, an indirect, wholly owned subsidiary of Bank of America ("BOA"), responsibility to provide certain subadministrative services to the Funds.

Columbia Management Distributors, Inc. ("CMDI"), a wholly owned subsidiary of BOA, is the Funds' principal underwriter and receives no compensation on the sale of Class Z shares.

Each Fund has adopted a Rule 12b-1 (distribution and service) plan which requires it to pay CMDI a monthly service fee equal to 0.25% annually of the average daily net assets attributable to Class A, Class B and Class C shares. The Rule 12b-1 plan also requires each fund to pay CMDI a monthly distribution fee equal to 0.50% and 0.75%, annually, of the average daily net assets attributable to Class B and Class C shares, respectively.

Columbia Management Services, Inc. (the "Transfer Agent"), a wholly owned subsidiary of BOA, provides shareholder services to the Funds. For such services, the Transfer Agent receives a fee, paid monthly, at the annual rate of $17.00 per open account. The Transfer Agent also receives reimbursement for certain out-of-pocket expenses and sub-transfer agency expenses. During the period January 1, 2007 through March 31, 2007, a portion of these fees were contractually waived.

Expenses waived by the Transfer Agent for the year ended December 31, 2007, were as follows:

(in thousands)
Columbia Acorn Fund	$	749
Columbia Acorn International		55
Columbia Acorn USA		67
Columbia Acorn International Select		4
Columbia Acorn Select		101
Columbia Thermostat Fund		11

70

Certain officers and trustees of the Trust are also officers of CWAM. The Trust makes no direct payments to its officers and trustees who are affiliated with CWAM.

The Board of Trustees appointed a Chief Compliance Officer for the Trust in accordance with federal securities regulations. The Funds, along with other affiliated funds, pay their pro-rata share of the expenses associated with the Office of the Chief Compliance Officer. Those expenses are disclosed separately as "Chief compliance officer expenses" in the Statements of Operations.

The Trust offers a deferred compensation plan for its independent trustees. Under that plan, a trustee may elect to defer all or a portion of his or her compensation. Amounts deferred are retained by the Trust and represent an unfunded obligation of the Trust. The value of amounts deferred is determined by reference to the change in value of Class Z shares of one or more series of the Trust or a money market fund as specified by the trustee. Benefits under the deferred compensation plan are payable when the trustee ceases to be a member of the Board of Trustees.

An affiliate may include any company in which a Fund owns five percent or more of its outstanding voting securities. On December 31, 2007, Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA and Columbia Acorn Select each held five percent or more of the outstanding voting securities of one or more companies. Details of investments in those affiliated companies are presented on pages 29, 30, 39, 47 and 56, respectively.

During the year ended December 31, 2007, the Funds engaged in purchase and sale transactions with funds that have a common investment adviser (or affiliated investment advisers), common directors/trustees, and/or common officers. Those transactions complied with Rule 17a-7 under the Investment Company Act of 1940 and were as follows:

	Purchases		Sales
(in thousands)
Columbia Acorn Fund	$	528	$	—
Columbia Acorn International		11,085		281
Columbia Acorn USA		115		—
Columbia Acorn Select		3,036		—

5.  Borrowing Arrangements

The Trust participates in a $150 million credit facility, which was entered into to facilitate portfolio liquidity. Interest is charged to each participating fund based on its borrowings at a rate per annum equal to the Federal Funds rate plus 0.50%. In addition, a commitment fee of 0.08% per annum of the unutilized line of credit is accrued and apportioned among the participating funds based on their relative net assets. The commitment fee is included in "Other expenses" in the Statements of Operations. No amounts were borrowed by any Fund under this facility for the year ended December 31, 2007.

6.  Investment Transactions

The aggregate cost of purchases and proceeds from sales other than short-term obligations for the year ended December 31, 2007, were:

Columbia Acorn Fund

(in thousands)
Investment securities
Purchases	$	4,733,104
Proceeds from sales		3,798,087

Columbia Acorn International

(in thousands)
Investment securities
Purchases	$	2,001,272
Proceeds from sales		1,409,352

Columbia Acorn USA

(in thousands)
Investment securities
Purchases	$	447,022
Proceeds from sales		341,275

Columbia Acorn International Select

(in thousands)
Investment securities
Purchases	$	175,176
Proceeds from sales		120,111

Columbia Acorn Select

(in thousands)
Investment securities
Purchases	$	1,010,135
Proceeds from sales		374,402

Columbia Thermostat Fund

(in thousands)
Investment securities
Purchases	$	234,732
Proceeds from sales		245,973

7.   Redemption Fees

For the year ended December 31, 2007, the redemption fees imposed by Columbia Acorn International and Columbia Acorn International Select amounted to $303,013 and $30,848, respectively, and are accounted for as additions to paid in capital.

8.   Other

For the year ended December 31, 2007, the Columbia Acorn Fund sustained two trading errors. Columbia Acorn Fund sold

71

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

shares of Enerflex Systems resulting in a loss of $364. Columbia Acorn Fund purchased shares of BioMarin resulting in a loss of $3,750. Additionally, for the year ended December 31, 2007, the Columbia Acorn USA sustained one trading error. Columbia Acorn USA purchased shares of Cavco Industries at a loss of $5,148.

The Funds were reimbursed by CWAM for the full amount of each loss.

9.   Legal Proceedings

The Trust, CWAM and the Trustees of the Trust (collectively, the "Columbia defendants") are named as defendants in class and derivative complaints that have been consolidated in a Multi-District Action (the "MDL Action") in the federal district court of Maryland. These lawsuits contend that defendants permitted certain investors to market time their trades in certain Columbia Acorn Funds. The MDL Action is ongoing. However, all claims against Columbia Acorn Trust and the independent trustees of the Trust have been dismissed.

The Trust and CWAM are also defendants in a class action lawsuit that alleges, in summary, that the Trust and CWAM exposed shareholders of Columbia Acorn International to trading by market timers by allegedly: (a) failing to properly evaluate daily whether a significant event affecting the value of the Fund's securities had occurred after foreign markets had closed but before the calculation of the Fund's net asset value ("NAV"); (b) failing to implement the Fund's portfolio valuation and share pricing policies and procedures; and (c) failing to know and implement applicable rules and regulations concerning the calculation of NAV (the "Fair Valuation Lawsuit"). The Seventh Circuit ruled that the plaintiffs' state law claims were preempted under federal law resulting in the dismissal of plaintiffs' complaint. Plaintiffs appealed the Seventh Circuit's ruling to the United States Supreme Court. The Supreme Court reversed the Sevent h Circuit's ruling on jurisdictional grounds and the case was ultimately remanded to the state court.

On March 21, 2005, a class action complaint was filed against the Columbia Acorn Trust and CWAM seeking to rescind the CDSC assessed upon redemption of Class B shares of Columbia Acorn Funds due to the alleged market timing of the Columbia Acorn Funds (the "CDSC Lawsuit"). In addition to the rescission of sales charges, plaintiffs seek recovery of actual damages, attorneys' fees and costs. The case had been transferred to the MDL Action in the federal district court of Maryland.

On September 14, 2007, the plaintiffs and the Columbia defendants named in the MDL Action, including the Columbia Funds, entered into a stipulation of settlement with respect to all Columbia-related claims in the MDL Action described above, including the CDSC and Fair Valuation Lawsuits. The settlement is subject to court approval.

CWAM, the Columbia Acorn Funds and the Trustees of the Trust are also defendants in a consolidated lawsuit filed in the federal district court of Massachusetts alleging that CWAM used Fund assets to make undisclosed payments to brokers as an incentive for the brokers to market the Funds over other mutual funds to investors. The complaint alleges CWAM and the Trustees of the Trust breached, along with certain affiliated entities and individuals, certain common law duties and federal laws.

On November 30, 2005, the judge dismissed all claims by plaintiffs and entered final judgment in favor of the defendants. The plaintiffs appealed to the United States Court of Appeals for the First Circuit on December 30, 2005. A stipulation and settlement agreement dated January 19, 2007 was filed in the First Circuit on February 14, 2007, with a joint stipulation of dismissal and motion for remand to obtain district court approval of the settlement. That joint motion was granted and the appeal was dismissed. On March 6, 2007, the case was remanded to the federal district court. The settlement, approved by the federal district court on September 18, 2007, became effective October 19, 2007. Pursuant to the settlement, the funds' adviser and/or its affiliates made certain payments, including plaintiffs' attorneys' fees and costs of notice to class members.

The Trust and CWAM intend to defend these suits vigorously.

As a result of these matters, or any adverse publicity or other developments resulting from them, there may be increased redemptions or reduced sales of Fund shares, which could increase transaction costs or operating expenses, or have other adverse consequences for the Funds. However, based on currently available information, the Columbia Acorn Trust believes that the likelihood that these lawsuits will have a material adverse impact on any fund is remote, and CWAM believes that the lawsuits are not likely to materially affect its ability to provide investment management services to the Funds.

72

Report of Independent Registered Public Accounting Firm

To the Board of Trustees and Shareholders of
Columbia Acorn Trust:

In our opinion, the accompanying statements of assets and liabilities, including the statements of investments, and the related statements of operations, changes in net assets and the financial highlights present fairly, in all material respects, the financial position of Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select and Columbia Thermostat Fund (each a series of Columbia Acorn Trust, hereinafter referred to as the "Funds") at December 31, 2007, the results of each of their operations for the year then ended, the changes in each of their net assets for each of the two years in the period then ended and the financial highlights for each of the four years in the period then ended, in conformity with accounting principles generally accepted in the United States of America. These financial statements and financial highlights (hereafter referred to as "financial statements") are the responsibility of the Funds' management; our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these financial statements in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits, which included confirmation of securities at December 31, 2007 by correspondence with the custodian and brokers, provide a reasonable basis for our opinion. The financial highlights of the Funds for the period ended December 31, 2003 wer e audited by other independent auditors whose report dated February 6, 2004 expressed an unqualified opinion on those financial statements.

PricewaterhouseCoopers LLP
Chicago, Illinois
February 20, 2008

73

Columbia Acorn Family of Funds

Federal Income Tax Information (in thousands) (unaudited) — Class A, B, C and Z shares

Columbia Acorn Fund

For the fiscal year ended December 31, 2007, the Fund designated long-term capital gains of $1,586,118.

80.06% of the ordinary income distributed by the Fund, for the year ended December 31, 2007, qualified for the corporate dividends received deduction.

For non-corporate shareholders 100.00%, or the maximum amount allowable under the Jobs and Growth Tax Relief Reconciliation Act of 2003, of income distributed by the Fund for the period January 1, 2007 to December 31, 2007 may represent qualified dividend income. Final information will be provided in your 2007 Form 1099-DIV.

Columbia Acorn International

For the fiscal year ended December 31, 2007, the Fund designated long-term capital gains of $458,971. Foreign taxes paid during the fiscal year ended December 31, 2007, amounting to $6,403 ($0.05 per share) are expected to be passed through to shareholders as 100% allowable foreign tax credits on Form 1099-DIV for the year ended December 31, 2007.

For non-corporate shareholders 100.00%, or the maximum amount allowable under the Jobs and Growth Tax Relief Reconciliation Act of 2003, of income distributed by the Fund for the period January 1, 2007 to December 31, 2007 may represent qualified dividend income. Final information will be provided in your 2007 Form 1099-DIV.

Gross income derived from sources within foreign countries amounted to $89,508 ($0.67 per share) for the fiscal year ended December 31, 2007.

Columbia Acorn USA

For the fiscal year ended December 31, 2007, the Fund designated long-term capital gains of $132,635.

Columbia Acorn International Select

Foreign taxes paid during the fiscal year ended December 31, 2007, amounting to $174 ($0.02 per share) are expected to be passed through to shareholders as 100% allowable foreign tax credits on Form 1099-DIV for the year ended December 31, 2007.

Gross income derived from sources within foreign countries amounted to $3,081 ($0.35 per share) for the fiscal year ended December 31, 2007.

5.77% of the ordinary income distributed by the Fund, for the year ended December 31, 2007, qualified for the corporate dividends received deduction.

For non-corporate shareholders 100.00%, or the maximum amount allowable under the Jobs and Growth Tax Relief Reconciliation Act of 2003, of income distributed by the Fund for the period January 1, 2007 to December 31, 2007 may represent qualified dividend income. Final information will be provided in your 2007 Form 1099-DIV.

Columbia Acorn Select

For the fiscal year ended December 31, 2007, the Fund designated long-term capital gains of $123,722.

83.92% of the ordinary income distributed by the Fund, for the year ended December 31, 2007, qualified for the corporate dividends received deduction.

For non-corporate shareholders 88.62%, or the maximum amount allowable under the Jobs and Growth Tax Relief Reconciliation Act of 2003, of income distributed by the Fund for the period January 1, 2007 to December 31, 2007 may represent qualified dividend income. Final information will be provided in your 2007 Form 1099-DIV.

Columbia Thermostat Fund

For the fiscal year ended December 31, 2007, the Fund designated long-term capital gains of $2,884.

4.71% of the ordinary income distributed by the Fund, for the year ended December 31, 2007, qualified for the corporate dividends received deduction.

For non-corporate shareholders 5.81%, or the maximum amount allowable under the Jobs and Growth Tax Relief Reconciliation Act of 2003, of income distributed by the Fund for the period January 1, 2007 to December 31, 2007 may represent qualified dividend income. Final information will be provided in your 2007 Form 1099-DIV.

74

[Excerpt from:]

Columbia Acorn Trust

Management Fee Evaluation of the Senior Officer

Prepared Pursuant to the New York Attorney General's
Assurance of Discontinuance

June 2007

75

Introduction

The New York Attorney General's Assurance of Discontinuance ("Order") entered into by Columbia Management Advisors, Inc. ("CMAI") and Columbia Management Distributors, Inc., ("CMDI" and collectively with "CMAI," "CMG") in February 2005, allows CMAI to manage or advise a mutual fund only if the trustees of the fund appoint a "Senior Officer" to perform specified duties and responsibilities. One of these responsibilities includes "managing the process by which proposed management fees (including but not limited to, advisory fees) to be charged the [Funds] are negotiated so that they are negotiated in a manner which is at arms' length and reasonable and consistent with this Assurance of Discontinuance."

This is the first year that the Columbia Acorn Trust and Wanger Advisors Trust (collectively, the "Trusts") and each series thereof (the "Acorn Funds," "WAT Funds" or collectively, the "Funds") have been overseen by the same Board of Trustees ("Board"). The Order provides that this Board must determine the reasonableness of proposed "management fees" by using either an annual competitive bidding process supervised by the Senior Officer or Independent Fee Consultant, or by obtaining "an annual independent written evaluation prepared by or under the direction of the Senior Officer or the Independent Fee Consultant."

"Management fees" are only part of the costs and expenses paid by mutual fund shareholders. The expenses can vary depending upon the class of shares held but usually include: (1) investment management or advisory fees to compensate analysts and portfolio managers for stock research and portfolio management, as well as the cost of operating a trading desk; (2) administrative expenses incurred to prepare registration statements and tax returns, calculate the Funds' net asset values, maintain effective compliance procedures and perform recordkeeping services; (3) transfer agency costs for establishing accounts, accepting and disbursing funds, as well as overseeing trading in Fund shares; (4) custodial expenses incurred to hold the securities purchased by the Funds; and (5) distribution expenses, including commissions paid to brokers that sell the Fund shares to investors.

Columbia Wanger Asset Management, L.P. ("CWAM"), the adviser to the Funds, has proposed that with respect to the Acorn Funds, the Columbia Acorn Trust continue the existing separate agreements governing the first two categories listed above: an advisory agreement governing portfolio management, and an administration agreement governing certain administration and clerical services. Together the fees paid under these two agreements are referred to as "management fees." CWAM proposes that the WAT Funds continue the existing single agreement governing both investment advisory and administrative services. A single management fee would cover both services. Other fund expenses are governed by separate agreements, in particular agreements with two CWAM affiliates: CMDI, the broker-dealer that underwrites and distributes the Funds' shares, and Columbia Management Services, Inc. ("CMSI"), the Funds' transfer agent. In conformity with the terms of the Order, this evaluation, therefore, addresses only the advisory and administrative contracts, and does not extend to the other agreements.

According to the Order, the Senior Officer's evaluation must consider at least the following:

(1)  Management fees (including components thereof) charged to institutional and other clients of CWAM for like services;

(2)  Management fees (including any components thereof) charged by other mutual fund companies for like services;

(3)  Costs to CWAM and its affiliates of supplying services pursuant to the management fee agreements, excluding any intra-corporate profit;

(4)  Profit margins of CWAM and its affiliates from supplying such services;

(5)  Possible economies of scale as the Funds grow larger; and

(6)  The nature and quality of CWAM's services, including the performance of each Fund.

In 2004, the Boards of the two Trusts, then separate groups, each appointed me Senior Officer under the Order. They also determined not to pursue a competitive bidding process and instead, charged me with the responsibility of evaluating the Funds' proposed advisory and administrative fee contracts with CWAM in conformity with the requirements of the Order. This Report is

76

an annual evaluation required under the Order. In discharging their responsibilities, the independent Trustees have also consulted independent, outside counsel.

2007 Evaluation

This is the third annual evaluation prepared in connection with the Order. This evaluation follows the same structure as the earlier studies. Some areas are given more emphasis here, while others are given less. Still, the fundamental information gathered for this evaluation is largely the same as past years.

Process and Independence

The objectives of the Order are to insure the independent evaluation of the advisory fees paid by the Funds as well as to insure that all relevant factors are considered. In my view, this contract renewal process has been conducted at arms-length and with independence in gathering, considering and evaluating all relevant data. At the outset of the process, the Trustees sought and obtained from CWAM and CMG a comprehensive compilation of data regarding Fund performance and expenses, adviser profitability, and other information. The Board evaluated this information thoroughly and also explored CWAM's potential capacity restraints. Performance and expense data was obtained from both Morningstar and Lipper, the leading consultants in this area. The rankings prepared by Morningstar and Lipper were independent and not influenced by the adviser. CWAM itself identified what it considers competing funds, and the Trustees considered that data as well.

In the course of its work, the Contract Committee gave careful consideration to the conclusions and recommendations contained in last year's evaluation. The Contract Committee gave particular emphasis to the issue of whether economies of scale were appropriately reflected in the Funds' fee schedules. Last year, the Board sought and CWAM agreed to additional breakpoints for two Funds, Acorn USA and Acorn Select. These breakpoints are above current asset levels, but clearly operate to share economies of scale with Fund shareholders. This year, at the Board's request, CWAM has proposed additional breakpoints for the WAT Funds, and Acorn International Select. This proposal is under consideration by the Board.

My evaluation of the advisory contract was shaped, as it was last year, by my experience as Chief Compliance Officer of the Trusts ("CCO"). As CCO, I report solely to the Board and have no reporting obligation to or employment relationship with CMG or its affiliates, except for administrative purposes. I have commented on compliance matters in evaluating the quality of service provided by CWAM.

This Report, its supporting materials and the data contained in other materials submitted to the Contract Committee of the Board, in my view, provide a thorough factual basis upon which the Board, in consultation with independent counsel as it deems appropriate, may conduct management fee negotiations that are in the best interests of the Funds' shareholders.

The Fee Reductions Mandated under the Order

Under the terms of the Order, CMG agreed to secure certain management fee reductions for the mutual funds advised by its affiliate investment advisers. In some instances, breakpoints were also established. Although neither CWAM nor the Trusts was a party to the Order, CWAM offered and the Board accepted certain advisory fee reductions during 2005. By the terms of the Order, these fees may not be increased before November 30, 2009. I have used these advisory fee levels— as modified last year to add certain breakpoints for Acorn USA and Acorn Select—in this evaluation because they are the fees in the current agreements that CWAM proposes should be continued. Hence, these fee levels are the starting point of an evaluation.

77

Conclusions

My review of the data and other material above leads to the following conclusions with respect to the factors identified in the Order.

1.  Performance. The domestic Funds generally have achieved outstanding performance. The Acorn Fund, Acorn USA, Acorn Select, Wanger Select and Wanger US Smaller Companies all rank very favorably against their peers over the past five years. Although Acorn USA and Wanger US Smaller Companies had a difficult year in 2006, these returns are not characteristic of these funds, both of which have shown improved performance during the first quarter of 2007. The international Funds have relatively weaker long term records than the domestic funds, but recently have improved significantly and their one year rankings are excellent. Overall then, performance of the Funds is excellent.

2.  Management Fees relative to Peers. The management fee rankings for several of the Acorn Funds are generally more favorable to shareholders than those of their peer group funds. Management fees do, however, vary by Fund. Acorn Fund is the least expensive and the Acorn USA the most expensive. Acorn Fund is very competitive, while Acorn USA and Acorn Select were ranked by both Lipper and Morningstar at or below the median, and therefore impose higher fees than do the majority of their competitors. The WAT Funds also lag their competitors and impose higher fees than their peers.

3.  Administrative Fees. The Acorn Funds' administrative fee, which is uniform across all Funds, is at a level comparable to or less expensive than the fees imposed by their peers, provides for appropriate services to Funds, and affords breakpoints that lower the fee as assets increase. The WAT Funds pay a single fee for advisory and administrative services and hence do not benefit from administrative fee breakpoints, nor is it possible to assess their administrative costs relative to competitors.

4.  Management Fees relative to Institutional and Other Mutual Fund Accounts. CWAM's focus is on its mutual funds. It does not actively seek to manage separate or institutional accounts. The few institutional accounts it does manage vary in rate structures. Some pay advisory fees commensurate with or higher than the Acorn and WAT Funds. In a few instances, however, institutional accounts pay lower advisory fees than do the Acorn Funds. One particular institutional account is significant in size and has been under CWAM's management for over 25 years.

5.  Costs to CWAM and its Affiliates. CWAM's direct costs do not appear excessive. Overhead and indirect costs allocated to CWAM by its parent organizations, however, are significant and increasing. CWAM's affiliates report operating losses and therefore do not appear to profit from CWAM's advisory agreement with the Funds.

6.  Profit Margins. CWAM's firm-wide, pre-marketing expense profit margins are at the top of the industry, though these comparisons are hampered by limited industry data. High profit margins are not unexpected for firms that manage large, successful funds and have provided outstanding investment performance for investors.

7.  Economies of Scale. Economies of scale do exist at CWAM and will expand as the assets of the Funds get larger. They are, however, only partially reflected in the management fee schedule for the Acorn Funds and not reflected at all in two of the four WAT Funds. Breakpoints above current asset levels have, however, been added to the more expensive funds, Acorn Select and Acorn USA. Nonetheless, if Fund assets continue to grow, under the Funds' current fee schedules, all Fund shareholders might not benefit in a manner generally commensurate with CWAM's increased profits. Management has proposed additional breakpoints for some of the Funds that, if implemented, would result in greater sharing of economies of scale.

78

8.  Nature and Quality of Services. This category includes a variety of considerations that are difficult to quantify, yet can have a significant bearing on the performance of the Acorn Funds. Several areas merit comment.

  a.  Capacity. The Funds have continued to grow, posing ever greater challenges in deploying assets effectively. While trends here merit continued monitoring, CWAM appears to be managing assets effectively.

  b.  Compliance. CWAM has a reasonably designed compliance program that protects shareholders.

  c.  Administrative Services. The Funds benefit from a variety of administrative services that are performed by CWAM and CMAI.

9.  Process. In my opinion, the process of negotiating an advisory contract for the Funds has been conducted thoroughly and at arms' length. Further, the Trustees have sufficient information to evaluate management's proposal, and negotiate contract terms that are in the best interests of fund shareholders.

Recommendations

(with respect to the Acorn Funds)

I believe the Trustees should:

1.  Continue to consider additional ways to restructure the advisory fee beyond the current breakpoint schedule to reflect more fully economies of scale.

2.  Continue to monitor CWAM's capacity limitations to insure that the Funds' expanding assets do not impair investment performance.

Robert P. Scales

Senior Vice President,
Chief Legal Officer
and General Counsel

June 18, 2007

79

Board Approval of the Advisory Agreement

Columbia Acorn Trust (the "Trust") has an investment advisory agreement (the "Agreement") with Columbia Wanger Asset Management, L.P. ("CWAM") under which CWAM manages the Columbia Acorn Funds (the "Funds"). The trustees of the Trust, more than seventy five percent of whom have never been affiliated with CWAM ("Independent Trustees"), oversee the management of each Fund and, as required by law, determine at least annually whether to continue the Agreement for each Fund.

The Contract Committee of the board of trustees (the "Committee"), which is comprised of six Independent Trustees, makes recommendations to the board regarding any proposed continuation of the Agreement. After the Committee has made its recommendation, the full board determines whether to approve the continuation of the Agreement. In addition, the board considers matters bearing on the Agreement at most of its other meetings throughout the year and meets at least quarterly with the portfolio managers employed by CWAM.

In connection with their most recent consideration of the Agreement for each Fund, the Committee and all trustees received and reviewed a substantial amount of information provided by CWAM in response to requests of the Independent Trustees and their counsel. Throughout their consideration of the Agreement, the Independent Trustees were advised by their independent legal counsel. At each of the meetings at which the Committee or the Independent Trustees considered the Agreement, they met with management and also met separately in executive session with their counsel.

The materials reviewed by the Committee and the trustees included, among other items, (i) information on the investment performance of each Fund and the performance of peer groups of funds and of the Fund's performance benchmarks, (ii) information on each Fund's advisory fees and other expenses, including information comparing the Fund's fees and expenses to those of peer groups of funds and information about any applicable expense limitations and fee "breakpoints," (iii) data on sales and redemptions of Fund shares and (iv) information on the profitability to CWAM and its affiliates of their relationships with the Funds and potential "fall-out" or ancillary benefits that CWAM and its affiliates may receive as a result of their relationships with the Funds. They also considered other information such as (i) CWAM's financial results and financial condition, (ii) each Fund's investment objective and strategies; (iii) the size, edu cation and experience of CWAM's investment staff and its use of technology, external research and trading cost measurement tools, (iv) the allocation of the Funds' brokerage, if any, including allocations to brokers affiliated with CWAM, and the use of "soft" commission dollars to pay for research products and services, (v) the resources devoted to, and the record of compliance with, the Funds' investment policies and restrictions, policies on personal securities transactions and other compliance policies and (vi) the economic outlook generally and for the mutual fund industry in particular. In addition, the trustees conferred with, and reviewed the Management Fee Evaluation (the "Fee Evaluation") prepared by, the Trust's chief compliance officer, who also serves as the Trust's "Senior Officer" as contemplated by the Assurance of Discontinuance dated February 9, 2005 among affiliates of CWAM and the Office of the New York Attorney General. A summary of the Fee Evaluation is included in this report. Throughou t the process, the trustees had the opportunity to ask questions of and request additional materials from CWAM.

On July 17, 2007, the board of trustees unanimously approved continuation of the Agreement through July 31, 2008, with an amendment to the fee schedule as described below. The approval followed Committee meetings held in February, May, June and July 2007.

In considering the continuation of the Agreement, the trustees reviewed and analyzed various factors that they determined were relevant, including the factors described below, none of which by itself was considered dispositive. However, the material factors and conclusions that formed the basis for the trustees' determination to approve the continuation of the Agreement are discussed separately below.

Nature, quality and extent of services. The trustees reviewed the nature, quality and extent of the services of CWAM and its affiliates to the Funds, taking into account the investment objective and strategy of each Fund and the knowledge the trustees gained from their regular meetings with management on at least a quarterly basis. In addition, the trustees reviewed the available resources and key personnel of CWAM and its affiliates, especially those who provide investment management services to the Funds. The trustees also considered other services provided to the Funds by CWAM and its affiliates, such as managing the execution of portfolio transactions and the selection of broker-dealers for those transactions, serving as the Funds' administrator, monitoring adherence to the Funds' investment restrictions, producing shareholder reports, providing s upport services for the board and board committees, communicating with shareholders and overseeing the activities of other service providers, including monitoring compliance

80

with various policies and procedures of the Funds and with applicable securities laws and regulations.

The trustees concluded that: the nature, quality and extent of the services provided by CWAM and its affiliates to each Fund were appropriate and consistent with the terms of the Agreement; that the quality of those services had been consistent with or superior to quality norms in the industry; and that the Funds were likely to benefit from the continued provision of those services. They also concluded that each of CWAM and its affiliates currently had sufficient personnel, with appropriate education and experience, to serve the Funds effectively and had demonstrated their continuing ability to attract and retain well qualified personnel.

Performance of the Funds. At various meetings of the board, of the Committee and of the board's investment performance analysis committee, the trustees considered the short-term and longer-term performance of each Fund. They reviewed information comparing each Fund's performance with the performance of the Fund's benchmark and with the performance of comparable funds and peer groups as identified by Lipper Inc. ("Lipper") and Morningstar Associates, LLC ("Morningstar"). They noted that, among the domestic Funds, Columbia Acorn Fund and Columbia Acorn Select had each outperformed its respective benchmark and Lipper and Morningstar peers for the relevant periods. Columbia Acorn USA suffered weak performance compared to its benchmark in 2006 and ranked toward the bottom of its peer group for that period. Notwithstanding that performance, that Fund's perf ormance approximated, or was ahead of, its benchmark for the most recent three, five and ten year periods. The trustees noted that Columbia Thermostat Fund had a limited performance history but was ranked high among its peers by Morningstar (but much less so by Lipper as a result of how Lipper classifies the Fund). The trustees also discussed the performance of the international Funds, noting that both of the international Funds had shown improvement over recent years. During the contract renewal process, the trustees concluded that, although past performance is not necessarily indicative of future results, the Funds' strong overall performance record was an important factor in the their evaluation of the quality of services provided by CWAM under the Agreement.

Costs of Services and Profits Realized by CWAM. At various Committee meetings and other informal meetings, the trustees examined detailed information on fees and expenses of each Fund in comparison to information for other comparable funds provided by Lipper and Morningstar. As noted in the Fee Evaluation, the contractual rates of investment advisory fees and the actual advisory fees for some of the Funds were higher than the median advisory fees of their respective peer groups (particularly with respect to Columbia Acorn USA and Columbia Acorn Select). The trustees also considered the management fees of the Acorn Funds relative to those of the Wanger Advisors Trust funds, a group of funds with similar investment strategies overseen by the same trustees and also managed by CWAM.

The Board and CWAM approved an amendment to the Agreement to establish additional breakpoints for Columbia Acorn International Select at 90 basis points for net asset levels over $500 million. The trustees determined that no other changes were necessary at this time in the fee schedules of the Funds.

The trustees reviewed the Fee Evaluation's analysis of the profitability of CWAM in serving as each Fund's investment adviser and of CWAM and its affiliates in all of their relationships with each Fund, as well as an explanation of the methodology utilized in allocating various expenses among the Funds and other business units. The trustees took into account the methodology used by CWAM in determining compensation payable to portfolio managers and the competitive environment for investment management talent. The trustees recognized that profitability comparisons among fund managers are difficult because very little comparative information is publicly available and the profitability of any manager is affected by numerous factors, including the organizational structure of the particular manager, the types of funds and other accounts it manages, possible other lines of business, the methodology for allocating expenses and the manag er's capital structure and cost of capital.

The trustees also reviewed CWAM's advisory fees for other investment companies, sub-advised funds and other institutional separate accounts, as detailed in the Fee Evaluation. In most instances its institutional separate account fees for various investment strategies were higher than the advisory fees charged to the Funds with corresponding strategies, although for a few accounts, the fees were lower. The trustees noted that CWAM performs significant additional services for the Funds that it does not provide to sub-advised funds or non-mutual fund clients, including administrative services, oversight of the Funds' other service providers, trustee support, regulatory compliance and numerous other services, and that, in servicing the Funds, CWAM assumes many legal risks that it does not assume in servicing

81

Board Approval of the Advisory Agreement, continued

many of its other clients. Finally, the trustees considered the financial condition of CWAM as part of the contract renewal process.

The trustees concluded that the rates of advisory fees (as amended for Columbia Acorn International Select) and other compensation payable by the Funds to CWAM and its affiliates were reasonable in relation to the nature and quality of the services to be provided, taking into account the fees charged by other advisers for managing comparable mutual funds with similar strategies and the fees CWAM charges to other clients. The trustees also concluded that the Funds' estimated overall expense ratios were reasonable, taking into account quality of services provided by CWAM and its affiliates and the investment performance of the Funds.

Economies of Scale. The trustees considered information about the potential for CWAM to realize economies of scale as a Fund's assets increase. They noted that the fee schedule for each Fund, other than Columbia Thermostat Fund, which is relatively modest in size, includes reductions in the rate of fees at various asset levels, including the newly established breakpoints for Columbia Acorn International Select. The trustees also noted that the Funds share directly in economies of scale through lower charges on third party service providers based on the combined scale of all of the Funds. Based on the information they reviewed, the trustees concluded that the current fee structure of each Fund was reasonable and that the current rates of fees do reflect a sharing between CWAM and the Funds of economies of scale.

Other Benefits to CWAM. The trustees also reviewed benefits that accrue to CWAM and its affiliates from their relationships with the Funds, as outlined in the Fee Evaluation. They recognized that two affiliates of CWAM separately serve the Funds as transfer agent and distributor, respectively, and that the transfer agent receives compensation from the Funds for services provided and that Columbia Management Distributors, Inc., the Funds' distributor, receives Rule 12b-1 fees, that are paid to broker-dealers. The trustees noted that, other than the services provided by CWAM and its affiliates pursuant to various agreements and the fees to be paid by each Fund therefor, the Funds and CWAM may potentially benefit from their relationship with each other in other ways. The trustees considered CWAM's use of commissions paid by each Fund on its portfolio bro kerage transactions to obtain research products and services benefiting the Fund and/or other clients of CWAM. The trustees determined that CWAM's use of the Funds' "soft" commission dollars to obtain research products and services was consistent with regulatory requirements and guidance then in effect. They also concluded that CWAM benefits from the receipt of proprietary research products and services acquired through commissions paid on portfolio transactions of the Funds and that the Funds benefit from CWAM's receipt of those products and services as well as research products and services acquired through commissions paid by other clients of CWAM. They further concluded that the success of any Fund could attract other business to CWAM or other Funds and that the success of CWAM could enhance its ability to serve the Funds.

After full consideration of the above factors as well as other factors that were instructive in evaluating the Agreement, the trustees, including the Independent Trustees, concluded that the continuation of the Agreement, as amended to revise the fee schedule for Columbia Acorn International Select, was in the best interest of each Fund. On July 17, 2007, the trustees continued the Agreement as so amended through July 31, 2008.

82

Board of Trustees and Management of
Columbia Acorn Funds

Each trustee may serve a term of unlimited duration until the end of the calendar year in which the trustee attains the age of 75 years. The trustees appoint their own successors, provided that at least two-thirds of the trustees, after such appointment, have been elected by shareholders. Shareholders may remove a trustee, with or without cause, upon the vote of two-thirds of the Trust's outstanding shares at any meeting called for that purpose. A trustee may be removed, with or without cause, upon the vote of a majority of the trustees. The names of the trustees and officers of Acorn, the date each was first elected or appointed to office, their principal business occupations during at least the last five years, number of portfolios in the fund complex they oversee, and other directorships they hold, are shown below. Each trustee serves in such capacity for each of the six series of Columbia Acorn Trust and for each of the four series of Wanger Advisors Trust.

The address for the trustees and officers of the Trust is Columbia Wanger Asset Management, L.P., 227 West Monroe Street, Suite 3000, Chicago, Illinois 60606. The Funds' Statement of Additional Information includes additional information about the Funds' trustees and officers. You may obtain a free copy of the Statement of Additional Information by writing or calling toll-free:

Columbia Wanger Asset Management, L.P.
Shareholder Services Group
227 W. Monroe, Suite 3000
Chicago IL 60606
1-800-922-6769

Name, Position(s) with Columbia Acorn and Age at December 31, 2007	Year First Elected or Appointed to Office*		Principal Occupation(s) during Past Five Years	Number of Portfolios in Fund Complex Overseen by Trustee/Officer		Other Directorships
Trustees who are not interested persons of Columbia Acorn:
Laura M. Born, 42, Trustee(1)		2007	Adjunct Assistant Professor of Finance, University of Chicago Graduate School of Business; Managing Director – Investment Banking, J.P. Morgan Chase & Co. Incorporated (broker-dealer) 1991-2007.		10	Wanger Advisors Trust
Maureen M. Culhane, 59, Trustee		2007	Retired; Vice President, Goldman, Sachs Asset Management L.P. (investment adviser) 2005; Vice President (Consultant) – Strategic Relationship Management, Goldman, Sachs & Co. 1999-2005; prior thereto, Vice President of Finance and Treasurer, Sara Lee Corporation.		10	Wanger Advisors Trust
Margaret Eisen, 54, Trustee		2002	Managing Director, CFA Institute since 2005; Chief Investment Officer, EAM International LLC (corporate finance and asset management) since 2003; prior thereto, Managing Director, DeGuardiola Advisors (investment bank); formerly Managing Director, North American Equities at General Motors Asset Management, and Director, Worldwide Pension Investments for DuPont Asset Management.		10	Antigenics, Inc. (biotechnology and pharmaceuticals); Wanger Advisors Trust
Jerome Kahn, Jr., 73, Trustee		1987	Portfolio manager and stock analyst and former President, William Harris Investors, Inc. (investment adviser).		10	Wanger Advisors Trust
Steven N. Kaplan, 48, Trustee		1999	Neubauer Family Professor of Entrepreneurship and Finance, Graduate School of Business, University of Chicago.		10	Morningstar, Inc. (provider of independent investment research); Wanger Advisors Trust
David C. Kleinman, 72, Trustee		1972	Adjunct Professor of Strategic Management, University of Chicago Graduate School of Business; business consultant.		10	Sonic Foundry, Inc. (rich media systems and software); Wanger Advisors Trust
Allan B. Muchin, 71, Trustee and Vice Chairman of the Board		1998	Chairman Emeritus, Katten Muchin Rosenman LLP (law firm).		10	Wanger Advisors Trust
Robert E. Nason, 71, Trustee and Chairman of the Board		1998	Consultant and private investor since 1998; formerly Executive Partner, Chief Executive Officer and member of the executive committee of Grant Thornton, LLP (public accounting firm) and member of the policy board of Grant Thornton International.		10	Wanger Advisors Trust
James A. Star, 46, Trustee		2006	President, Longview Asset Management LLC (investment adviser) since 2003, prior thereto, portfolio manager; Vice President, Henry Crown and Company (investment firm); President and Chief Investment Officer, Star Partners (hedge fund) from 1998 to 2003.		10	Wanger Advisors Trust

83

Name, Position(s) with Columbia Acorn and Age at December 31, 2007	Year First Elected or Appointed to Office*		Principal Occupation(s) during Past Five Years	Number of Portfolios in Fund Complex Overseen by Trustee/Officer		Other Directorships
Trustees who are not interested persons of Columbia Acorn: (continued)
John A. Wing, 72, Trustee		2002	Partner, Dancing Lion Partners (investment partnership); prior thereto, Frank Wakely Gunsaulus Professor of Law and Finance, and Chairman of the Center for the Study of Law and Financial Markets, Illinois Institute of Technology; formerly Chairman of the Board and Chief Executive Officer of ABN-AMRO Incorporated (formerly named The Chicago Corporation, a financial services firm) and Chief Executive Officer of Market Liquidity Network, LLC.		10	First Chicago Bank and Trust; First Chicago Bancorp; Wanger Advisors Trust
Trustees who are interested persons of Columbia Acorn:
Charles P. McQuaid, 53, Trustee and President(2)		1992	President and Chief Investment Officer, CWAM since October 2003; portfolio manager since 1995 and Director of Research, CWAM and its predecessor from July 1992 through December 2003; Interim Director of International Research, CWAM from October 2003 to December 2004; President of Wanger Advisors Trust since 2003.		10	Wanger Advisors Trust
Ralph Wanger, 72, Trustee(3)		1970	Founder, former President, Chief Investment Officer and portfolio manager, CWAM from July 1992 to September 2003; former President, Columbia Acorn Trust from April 1992 through September 2003; former President, Wanger Advisors Trust 1994 through September 2003; Director, Wanger Investment Company PLC; advisor to CWAM from September 2003 to September 2005.		10	Wanger Advisors Trust
Officers of Columbia Acorn:
Ben Andrews, 41, Vice President		2004	Analyst and portfolio manager, CWAM since 1998; Vice President, Wanger Advisors Trust.		10	None
Michael G. Clarke, 38, Assistant Treasurer		2004	Assistant Treasurer, Wanger Advisors Trust; Chief Accounting Officer and Assistant Treasurer of the Columbia Funds since October 2004; Director of Fund Administration of Columbia Management Advisors, LLC since January 2006; Managing Director of Columbia Management Advisors, LLC from September 2004 to December 2005; Vice President, Fund Administration of Columbia Management Advisors, LLC from June 2002 to September 2004.		10	None
Jeffrey Coleman, 38, Assistant Treasurer		2006	Assistant Treasurer, Wanger Advisors Trust since March 2006; Director of Fund Administration, CWAM since January 2006; Fund Controller, CWAM from October 2004 to January 2006; Vice President of CDC IXIS Asset Management Services, Inc. (investment management) from August 2000 to September 2004.		10	None
J. Kevin Connaughton, 43, Assistant Treasurer		2001	Treasurer and Chief Financial Officer of the Columbia Funds since December 2000; Vice President of Columbia Management Advisors, LLC since April 2003; Assistant Treasurer of Wanger Advisors Trust since 2001; Treasurer and Chief Financial Officer of the Liberty Funds, Stein Roe Funds and Liberty All-Star Funds from December 2000 to December 2006; Treasurer of the Galaxy Funds from September 2002 through November 2005; Treasurer of Columbia Management Multi-Strategy Hedge Fund, LLC from December 2002 through December 2004; and a senior officer of various affiliated entities of the Bank of America Corporation, including other registered and unregistered funds.		10	None

84

Name, Position(s) with Columbia Acorn and Age at December 31, 2007	Year First Elected or Appointed to Office*		Principal Occupation(s) during Past Five Years	Number of Portfolios in Fund Complex Overseen by Trustee/Officer		Other Directorships
Officers of Columbia Acorn: (continued)
P. Zachary Egan, 39, Vice President		2003	Director of International Research, CWAM, since December 2004; portfolio manager, CWAM since 2003; analyst, CWAM since 1999.		10	None
Peter T. Fariel, 50, Assistant Secretary		2006	Associate General Counsel, Bank of America since April 2005; prior thereto, Partner, Goodwin Procter LLP (law firm).		10	None
John Kunka, 37, Assistant Treasurer		2006	Director of Accounting and Operations, CWAM, since 2006; Assistant Treasurer, Wanger Advisors Trust, since 2006; Manager of Mutual Fund Operations, Calamos Advisors, Inc. from 2005 to 2006; prior thereto, Manager of Mutual Fund Administration, Van Kampen Investments.		10	None
Joseph LaPalm, 37, Vice President		2006	Chief Compliance Officer, CWAM since 2005; Vice President, Wanger Advisors Trust since 2006; prior thereto, Compliance Officer, William Blair & Company (investment firm).		10	None
Bruce H. Lauer, 50, Vice President, Secretary and Treasurer		1995	Chief Operating Officer, CWAM since April 2000; Vice President, Treasurer and Secretary, Wanger Advisors Trust; Director, Wanger Investment Company PLC; Director, Banc of America Capital Management (Ireland) Ltd.; Director, Bank of America Global Liquidity Fund PLC.		10	None
Louis J. Mendes, 43, Vice President		2003	Analyst and portfolio manager, CWAM since 2001; Vice President, Wanger Advisors Trust.		10	None
Robert A. Mohn, 46, Vice President		1997	Analyst and portfolio manager, CWAM since August 1992; Director of Domestic Research, CWAM since March 2004; Vice President, Wanger Advisors Trust.		10	None
Christopher Olson, 43, Vice President		2001	Analyst and portfolio manager, CWAM since January 2001; Vice President, Wanger Advisors Trust.		10	None
Robert Scales, 55, Chief Compliance Officer, Chief Legal Officer, Senior Vice President and General Counsel		2004	Chief Compliance Officer, Senior Vice President, Chief Legal Officer and General Counsel, Wanger Advisors Trust since 2004; prior thereto, Associate General Counsel, Grant Thornton LLP.		10	None
Linda Roth-Wiszowaty, 38, Assistant Secretary		2006	Business support analyst, CWAM since April 2007; Assistant Secretary, Wanger Advisors Trust; executive administrator, CWAM since April 2004; prior thereto, executive assistant to the Chief Operating Officer, CWAM.		10	None

*  Dates prior to April 1992 correspond to the date of first election or appointment as a director of officer of The Acorn Fund, Inc., the Trust's predecessor.

(1)  Effective January 1, 2008, Trustee is no longer treated as an "interested person," as defined in the Investment Company Act of 1940, as amended (the "1940 Act"). Prior to January 1, 2008, Trustee was considered an "interested person" of the Trust and of CWAM, as defined in the 1940 Act, as a result of her previous affiliation with J.P. Morgan Chase & Co. Incorporated, a registered broker-dealer that may execute portfolio transactions for or engage in principal transactions with the Funds or other clients or funds advised by CWAM or its affiliates.

(2)  Trustee who is an "interested person" of the Trust and of CWAM, as defined in the 1940 Act, because he is an officer of the Trust and of CWAM.

(3)  Trustee who is treated as an "interested person" of the Trust and of CWAM, as defined in the 1940 Act, because he is a former officer of the Trust and former employee of and consultant to CWAM.

85

Columbia Acorn Family of Funds

Class Z Share Information

Minimum Initial Investment in Columbia Acorn International, Columbia Acorn International Select and Columbia Thermostat Fund		$2,500† $1,000 for an IRA
Minimum Initial Investment in Columbia Acorn Fund and Columbia Acorn USA	$	75,000	†
Minimum Initial Investment in Columbia Acorn Select	$	100,000	*†
Minimum Subsequent Investment in all Funds	$	50
Exchange Fee		None

Columbia Acorn Fund	ACRNX
Management Fee	0.64	%
12b-1 Fee	None
Other Expenses	0.10	%
Net Expense Ratio	0.74	%
Columbia Acorn International	ACINX
Management Fee	0.76	%
12b-1 Fee	None
Other Expenses	0.15	%
Net Expense Ratio	0.91	%
Columbia Acorn USA	AUSAX
Management Fee	0.86	%
12b-1 Fee	None
Other Expenses	0.12	%
Net Expense Ratio	0.98	%
Columbia Acorn International Select	ACFFX
Management Fee	0.94	%
12b-1 Fee	None
Other Expenses	0.24	%
Net Expense Ratio	1.18	%
Columbia Acorn Select	ACTWX
Management Fee	0.79	%
12b-1 Fee	None
Other Expenses	0.12	%
Net Expense Ratio	0.91	%
Columbia Thermostat Fund	COTZX
Management Fee	0.10	%
12b-1 Fee	None
Other Expenses	0.15	%**
Net Expense Ratio	0.25	%

    Fees and expenses are for the twelve months ended December 31, 2007, and for Columbia Thermostat Fund include the effect of Columbia Wanger Asset Management's undertaking to waive fees and/or reimburse the Fund for any ordinary operating expenses (exclusive of interest and fees on borrowings, and expenses associated with the Fund's investment in other investment companies, but including custodial charges relating to overdrafts, if any), after giving effect to any balance credits from the Fund's custodian in excess of the annual rate of 0.25% of the average daily net assets. Columbia Thermostat Fund's reimbursement arrangement is contractual through April 30, 2008. The Funds' adviser and/or affiliates had agreed to contractually waive a portion of "other expenses" through March 31, 2007.

  *  Effective June 25, 2007, the board of trustees voted to increase the minimum initial investment for Columbia Acorn Select from $50,000 to $100,000.

  **  Does not include estimated fees and expenses of 0.70% incurred by the Fund from the underlying funds in which it invests.

  †  Certain exclusions may apply.

86

Columbia Acorn Family of Funds

Investment Adviser

Columbia Wanger Asset Management, L.P.
227 West Monroe Street, Suite 3000
Chicago, Illinois 60606

1-800-922-6769

Distributor

Columbia Management Distributors, Inc.
One Financial Center
Boston, Massachusetts 02111-2621

Transfer Agent, Dividend Disbursing Agent

Columbia Management Services, Inc.
P. O. Box 8081
Boston, Massachusetts 02266-8081

1-800-345-6611

Legal Counsel

Bell, Boyd & Lloyd LLP
Chicago, Illinois

Independent Registered Public Accounting Firm

PricewaterhouseCoopers LLP
Chicago, Illinois

This report, including the schedules of investments, submitted for the general information of the shareholders of Columbia Acorn Trust. This report is not authorized for distribution unless preceded or accompanied by a prospectus. An investor should carefully consider charges and expenses before investing. To obtain a prospectus containing this and other information, please call 800-922-6769 or visit our website (shown below). Please read the prospectus carefully before you invest or send money.

A description of the policies and procedures that the Funds use to determine how to vote proxies and a copy of the Funds' voting record are available (i) without charge, upon request, by calling 800-922-6769 and (ii) on the Securities and Exchange Commission's website at www.sec.gov. Information regarding how the Funds voted proxies relating to portfolio securities during the 12-month period ended June 30, is available from the SEC's website. Information regarding how the Funds voted proxies relating to portfolio securities is also available at http://institutional.columbiamanagement.com.

The Funds file a complete schedule of portfolio holdings with the SEC for the first and third quarters of each fiscal year on Form N-Q. The Funds' Form N-Q is available on the SEC's website at www.sec.gov and may be reviewed and copied at the SEC's Public Reference Room in Washington, D.C. Information on the operation of the Public Reference Room may be obtained by calling 1-800-SEC-0330.

Investors should carefully consider the investment objectives, risks, charges and expenses for any Columbia fund before investing. Contact your Columbia Management representative for a prospectus, which contains this and other important information about the Fund. Read it carefully before investing.

Columbia Management Group, LLC ("Columbia Management") is the investment management division of Bank of America Corporation. Columbia Management entities furnish investment management services and products for institutional and individual investors. Columbia Funds are distributed by Columbia Management Distributors, Inc., member of FINRA, SIPC, part of Columbia Management and an affiliate of Bank of America Corporation. Columbia Wanger Asset Management, L.P. ("CWAM") is an SEC-registered investment adviser and indirect, wholly owned subsidiary of Bank of America Corporation. CWAM is part of Columbia Management.

Find out what's new – visit our web site at:

www.columbiafunds.com

Our e-mail address is:

ServiceInquiries@ColumbiaManagement.com

Shareholders should not include personal information such as account numbers, Social Security numbers or taxpayer identification numbers in e-mail. We are unable to accept account transactions sent via e-mail.

87

Columbia Acorn Family of Funds

Class Z Shares

Annual Report – December 31, 2007

Columbia Management_®

PRESORTED

FIRST-CLASS MAIL

U.S. POSTAGE PAID

HOLLISTON, MA

PERMIT NO. 20

©2008 Columbia Management Distributors, Inc.

One Financial Center, Boston, MA 02111-2621

800-345-6611 www.columbiafunds.com

SHC-43/139014-1207 (02/08) 08/49897

4Q

Columbia Acorn
Family of Funds

Class A, B and C Shares

Annual Report

December 31, 2007

n  Columbia^SM
Acorn® Fund

n  Columbia^SM
Acorn International®

n  Columbia^SM
Acorn USA®

n  Columbia^SM
Acorn International Select^SM

n  Columbia^SM
Acorn Select^SM

n  Columbia^SM
Thermostat Fund^SM

Managed by Columbia Wanger Asset Management, L.P.

NOT FDIC INSURED

NOT BANK ISSUED

May Lose Value

No Bank Guarantee

Columbia Acorn Family of Funds

Net Asset Value Per Share as of 12/31/07

	Columbia Acorn Fund		Columbia Acorn International		Columbia Acorn USA		Columbia Acorn International Select		Columbia Acorn Select		Columbia Thermostat Fund
Class A	$	28.87	$	43.42	$	27.23	$	31.74	$	27.89	$	12.31
Class B	$	27.39	$	42.46	$	25.87	$	30.50	$	26.57	$	12.38
Class C	$	27.25	$	42.32	$	25.77	$	30.42	$	26.46	$	12.37

2007 Year-End Distributions

The following table details the Funds' year-end distributions. The record date for all Funds except Columbia Thermostat Fund was December 10, 2007. The ex-dividend date was December 11, 2007, and the payable date was December 12, 2007. For Columbia Thermostat Fund, the record date was December 20, 2007. The ex-dividend date was December 21, 2007, and the payable date was December 24, 2007.

	Short-term Capital Gains		Long-term Capital Gains		Ordinary Income		Reinvestment Price
Columbia Acorn Fund Class A	$	0.1126	$	1.8022	$	0.0242	$	29.04 —	A
Columbia Acorn Fund Class B and C	$	0.1126	$	1.8022		None	$	27.56 —	B
							$	27.42 —	C
Columbia Acorn International Class A	$	0.1785	$	2.9312	$	0.0806	$	43.84 —	A
Columbia Acorn International Class B and C	$	0.1785	$	2.9312		None	$	42.88 —	B
							$	42.75 —	C
Columbia Acorn USA Class A, B and C		None	$	1.4262		None	$	27.29 —	A
							$	25.93 —	B
							$	25.83 —	C
Columbia Acorn International Select Class A		None	$	1.7656	$	0.0451	$	31.79 —	A
Columbia Acorn International Select Class B and C		None	$	1.7656		None	$	30.57 —	B
							$	30.48 —	C
Columbia Acorn Select Class A, B and C		None	$	0.4558		None	$	28.10 —	A
							$	26.78 —	B
							$	26.67 —	C
Columbia Thermostat Fund Class A	$	0.3907	$	0.1072	$	0.4738	$	12.28 —	A
Columbia Thermostat Fund Class B	$	0.3907	$	0.1072	$	0.4088	$	12.35 —	B
Columbia Thermostat Fund Class C	$	0.3907	$	0.1072	$	0.3763	$	12.35 —	C

The views expressed in the "Letter to Shareholders," "Squirrel Chatter II" and "In a Nutshell" commentary reflect the current views of the respective authors. These views are not guarantees of future performance and involve certain risks, uncertainties and assumptions that are difficult to predict so actual outcomes and results may differ significantly from the views expressed. These views are subject to change at any time based upon economic, market or other conditions and the respective parties disclaim any responsibility to update such views. These views may not be relied on as investment advice and, because investment decisions for a Columbia Acorn Fund are based on numerous factors, may not be relied on as an indication of trading intent on behalf of any particular Columbia Acorn Fund. References to specific company securities should not be construed as a recommendation or investment advice and there can be no assurance that as of the date of publication of this report, the securities mentioned in each Fund's portfolio are still held or that the securities sold have not been repurchased.

Letter to Shareholders from the
Columbia Acorn Trust Board of Trustees

The Columbia Acorn Trust Board of Trustees has 10 independent Trustees and Ralph Wanger, the retired founder of the predecessor company of Columbia Wanger Asset Management ("CWAM"), the investment adviser of the Columbia Acorn Family of Funds ("Acorn Funds"). Charles P. McQuaid, the Chief Investment Officer of CWAM, is also a Trustee. This diverse and qualified complement of shareholder Trustees with a strong independent majority provides the foundation of a decision process without undue influence of conflicting interests.

Governance of the Acorn Funds is driven through an active committee structure. The issues and challenges we face in today's environment can be complex and frequently require an in-depth review and analysis by committee. Our governance process is more efficient and effective when issues are studied in-depth in preparation of making a recommendation for consideration by the full Board of Trustees.

The function and purpose of each standing committee of the Board of Trustees that meets regularly is specified in the committee's charter. Trustees and chairpersons are nominated and elected to these committees based on their background and experience to meet the purpose and objective of the respective committee with recognition of a preference to achieve some balance of the workload among all Trustees. Committees that meet regularly are Audit, Compliance, Contract, Governance, Investment Performance and Valuation. All chairpersons are independent trustees with the exception of the Valuation committee which is chaired by Charles P. McQuaid. In addition to our standing committees, we have in the past established limited purpose committees, and are prepared to do so in the future to review and analyze specific issues or topics as they arise.

The Trustees initiated and approved changes relating to certain Acorn Funds during the year.

•  Approved a strategy for Acorn Select Fund generally to invest in 30 to 60 companies (up from 20 to 40 companies) with market capitalizations under $20billion. We also increased the limit for the Fund's investment in non U.S. based companies to 33% from 25%.

•  Established a new advisory fee breakpoint for Acorn International Select Fund for total assets of $500 million and over at .90%, a reduction from .94%.

•  We discontinued the sale of Class B shares of all Acorn Funds with the exception of dividend reinvestments, effective February 29, 2008.

•  The minimum investment for new shareholders in the Acorn Select Fund was increased to $100,000 from $50,000.

One critical responsibility of your Board of Trustees is to have a complement of Trustees to achieve multiple objectives including planned succession and continuity in the future. Two new independent Trustees were elected by the Board in 2007: Laura A. Born and Maureen M. Culhane. They are exceptionally qualified for your Board.

At the conclusion of our September, 2007 meeting, Patricia A.Werhane, an independent Trustee, concluded her term of service on the Board. On behalf of all shareholders we thank her for her commitment and outstanding service to the Acorn Funds.

As we begin a new year, your Trustees are confident that the investment management responsibilities for the Acorn Funds are in strong hands. We have renewed the investment advisory agreement for each of the Acorn Funds with CWAM through July 2008 and have again placed our trust in CWAM's aim to meet shareholder expectations. Consistency and continuity have always been a key strength of CWAM and its predecessors in serving the Acorn Funds. CWAM is led by Charles P. McQuaid. He has been serving the Acorn Funds for over 29 consecutive years. He is surrounded by a group of talented portfolio managers, some who joined him in serving the Acorn Funds in the 1990's and others in more recent years.

Accompanying this letter is the 2007 annual report to shareholders of the Acorn Funds that includes performance information from your portfolio managers. We thank our fellow shareholders for their interest and investment in the Acorn Funds.

Robert E. Nason
Independent Chairman of the Board of Trustees
Columbia Acorn Trust

Columbia Acorn Family of Funds

Table of Contents

Descriptions of Indexes	1
Share Class Performance	2
Fund Performance vs. Benchmarks	3
Squirrel Chatter II: Ponzi Schemes and Politicians' Dreams	4
Understanding Your Expenses	6
Columbia Acorn Fund
In a Nutshell	8
At a Glance	9
Major Portfolio Changes	20
Statement of Investments	22
Columbia Acorn International
In a Nutshell	10
At a Glance	11
Major Portfolio Changes	34
Statement of Investments	36
Portfolio Diversification	42
Columbia Acorn USA
In a Nutshell	12
At a Glance	13
Major Portfolio Changes	43
Statement of Investments	44
Columbia Acorn International Select
In a Nutshell	14
At a Glance	15
Major Portfolio Changes	50
Statement of Investments	51
Portfolio Diversification	54

Columbia Acorn Select
In a Nutshell	16
At a Glance	17
Major Portfolio Changes	55
Statement of Investments	56
Columbia Thermostat Fund
In a Nutshell	18
At a Glance	19
Statement of Investments	59
Columbia Acorn Family of Funds
Statements of Assets and Liabilities	60
Statements of Operations	61
Statements of Changes in Net Assets	62
Financial Highlights	66
Notes to Financial Statements	72
Report of Independent Registered Public Accounting Firm	79
Federal Income Tax Information	80
Management Fee Evaluation of the Senior Officer	81
Board Approval of the Advisory Agreement	86
Board of Trustees and Management of Columbia Acorn Funds	89
Class A, B and C Share Information	92
Columbia Acorn Family of Funds Information	93

Columbia Acorn Family of Funds

Descriptions of indexes included in this report:

•Standard & Poor's (S&P) 500 Index tracks the performance of 500 widely held, large-capitalization U.S. stocks.

•Standard & Poor's (S&P) MidCap 400 Index is a market value-weighted index that tracks the performance of 400 mid-cap U.S. companies.

•Russell 2000® Index measures the performance of the 2,000 smallest companies in the Russell 3000 Index, which represents approximately 8% of the total market capitalization of the Russell 3000 Index.

•Russell 2500^TM Index measures the performance of the 2,500 smallest companies in the Russell 3000 Index, which represents approximately 17% of the total market capitalization of the Russell 3000 Index.

•S&P/Citigroup EMI Global ex-US Index is an unmanaged index consisting of the bottom 20% of institutionally investable capital of developed and emerging countries, outside the United States.

•S&P/Citigroup Global ex-US Cap Range $500mm-$5bn Index is a subset of the broad market selected by the index sponsor representing the mid- and small-cap developed and emerging markets, excluding the United States.

•Morgan Stanley Capital International Europe, Australia, Far East (MSCI EAFE) Index is a capitalization-weighted index that tracks the total return of common stocks in 21 developed-market countries within Europe, Australia and the Far East.

•S&P/Citigroup World ex-US Cap Range $2–10B Index is a subset of the broad market selected by the index sponsor representing the mid-cap developed market excluding the United States.

•Lipper Indexes include the largest funds tracked by Lipper, Inc. in the named category. Lipper Mid-Cap Growth Index, 30 mid-cap growth funds; Lipper Mid-Cap Core Funds Index, 30 mid-cap core funds; Lipper International Funds Index, 30 largest non-U .S. funds, not including non-U.S. small-cap funds; Lipper International Small-Cap Funds Index, 10 largest non-U.S. funds investing in small-cap companies, including Columbia Acorn International; Lipper Small-Cap Core Funds Index, 30 largest small-cap core funds, including Columbia Acorn Fund; Lipper Flexible Portfolio Funds Index, an equal dollar-weighted index of the 30 largest mutual funds within the Flexible Portfolio fund classification, as defined by Lipper.

•Lehman Brothers U.S. Credit Intermediate Bond Index is the intermediate component of the U.S. Credit Index. The U.S. Credit Index includes publicly issued U.S. corporate and foreign debentures and secured notes that meet specified maturity, liquidity, and quality requirements.

Unlike mutual funds, indexes are not managed and do not incur fees or expenses. It is not possible to invest directly in an index.

1

Columbia Acorn Family of Funds

Share Class Performance Average Annual Total Returns through 12/31/07

	Class A						Class B						Class C
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Columbia Acorn Fund (10/16/00)
3 months*		-3.30	%		-8.86	%		-3.42	%		-7.93	%		-3.47	%		-4.37	%
1 year		7.39	%		1.22	%		6.76	%		1.83	%		6.56	%		5.58	%
3 years		11.39	%		9.21	%		10.69	%		9.86	%		10.53	%		10.53	%
5 years		19.37	%		17.96	%		18.58	%		18.38	%		18.49	%		18.49	%
Life of fund		12.69	%		11.77	%		11.96	%		11.96	%		11.89	%		11.89	%
Columbia Acorn International (10/16/00)
3 months*		-2.10	%		-7.73	%		-2.21	%		-6.77	%		-2.28	%		-3.20	%
1 year		16.90	%		10.17	%		16.25	%		11.25	%		16.01	%		15.01	%
3 years		23.95	%		21.52	%		23.16	%		22.49	%		22.99	%		22.99	%
5 years		29.25	%		27.73	%		28.40	%		28.25	%		28.31	%		28.31	%
Life of fund		11.88	%		10.97	%		11.15	%		11.15	%		11.09	%		11.09	%
Columbia Acorn USA (10/16/00)
3 months*		-3.30	%		-8.86	%		-3.46	%		-8.03	%		-3.47	%		-4.38	%
1 year		3.18	%		-2.75	%		2.53	%		-2.28	%		2.39	%		1.43	%
3 years		7.87	%		5.76	%		7.15	%		6.28	%		7.03	%		7.03	%
5 years		17.13	%		15.75	%		16.35	%		16.13	%		16.27	%		16.27	%
Life of fund		12.10	%		11.19	%		11.38	%		11.38	%		11.33	%		11.33	%
Columbia Acorn International Select (10/16/00)
3 months*		0.74	%		-5.05	%		0.57	%		-4.19	%		0.54	%		-0.41	%
1 year		21.50	%		14.51	%		20.69	%		15.69	%		20.53	%		19.53	%
3 years		24.07	%		21.64	%		23.27	%		22.61	%		23.10	%		23.10	%
5 years		27.24	%		25.74	%		26.40	%		26.24	%		26.30	%		26.30	%
Life of fund		9.62	%		8.73	%		8.88	%		8.88	%		8.84	%		8.84	%
Columbia Acorn Select (10/16/00)
3 months*		-5.34	%		-10.78	%		-5.48	%		-10.13	%		-5.50	%		-6.43	%
1 year		8.92	%		2.66	%		8.22	%		3.22	%		8.04	%		7.04	%
3 years		12.92	%		10.71	%		12.17	%		11.37	%		12.02	%		12.02	%
5 years		17.19	%		15.81	%		16.40	%		16.18	%		16.30	%		16.30	%
Life of fund		12.39	%		11.47	%		11.64	%		11.64	%		11.58	%		11.58	%
Columbia Thermostat Fund (3/3/03)†
3 months*		0.26	%		-5.51	%		0.22	%		-4.45	%		0.04	%		-0.89	%
1 year		8.19	%		1.97	%		7.71	%		2.80	%		7.36	%		6.38	%
3 years		7.98	%		5.87	%		7.37	%		6.55	%		7.17	%		7.17	%
Life of fund		11.43	%		10.07	%		10.77	%		10.49	%		10.61	%		10.61	%

*Not annualized.

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in a Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Please visit columbiafunds.com for daily and most recent month-end performance updates.

The "with sales charge" returns include the maximum initial sales charge of 5.75% for Class A shares, the applicable contingent deferred sales charge (CDSC) for Class B shares (5%, 4%, 3%, 3%, 2%, 1%, 0% for the first through seventh years after purchase, respectively), and the maximum CDSC of 1.00% of Class C shares during the first year after purchase.

Annual operating expense ratios are as stated in each Fund's prospectus that is current as of the date of this report. Differences in expense ratios disclosed elsewhere in this report may result from including fee waivers and reimbursements as well as different time periods used in calculating the ratios. Columbia Acorn Fund: Class A: 1.05%; Class B: 1.63%; Class C: 1.84%. Columbia Acorn International: Class A: 1.27%; Class B: 1.86%; Class C: 2.05%. Columbia Acorn USA: Class A: 1.30%; Class B: 1.89%; Class C: 2.09%. Columbia Acorn International Select: Class A: 1.63%; Class B: 2.23%; Class C: 2.42%. Columbia Acorn Select: Class A: 1.27%; Class B: 1.88%; Class C: 2.08%. Columbia Thermostat Fund has a contractual expense waiver or reimbursement that expires April 30, 2008. Expense ratios without and with the contractual waiver, including fees and expenses associated with the Fund's investments in other investment companies are: Class A: 1.35%, 1.19%; Class B: 1.88%, 1.69%; Class C: 2.15%, 1.94%, respectively.

Performance results reflect any waivers or reimbursements of Fund expenses by the investment adviser and/or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results would have been lower.

†A "fund of funds" bears its allocable share of the costs and expenses of the underlying funds in which it invests. Such funds are thus subject to two levels of fees and potentially higher expense ratios than would be associated with an investment in a fund that invests and trades directly in financial instruments under the direction of a single manager.

All results shown assume reinvestment of distributions and do not reflect the deduction of taxes that a shareholder would pay on fund distributions or the redemption of fund shares.

2

Columbia Acorn Family of Funds

Fund Performance vs. Benchmarks Class A Shares, without sales charge,
Average Annual Total Returns through 12/31/07

	4th quarter*			1 year			3 years			5 years			Life of Fund
Columbia Acorn Fund (LACAX) (10/16/00)		-3.30	%		7.39	%		11.39	%		19.37	%		12.69	%
Russell 2500		-4.32	%		1.38	%		8.38	%		16.99	%		9.18	%
S&P 500		-3.33	%		5.49	%		8.62	%		12.83	%		2.67	%
Lipper Small-Cap Core Funds Index		-4.23	%		1.92	%		7.62	%		15.76	%		8.81	%
Lipper Mid-Cap Core Funds Index		-3.44	%		6.34	%		9.71	%		15.80	%		6.95	%
Columbia Acorn International (LAIAX) (10/16/00)		-2.10	%		16.90	%		23.95	%		29.25	%		11.88	%
S&P/Citigroup EMI Global ex-US		-3.36	%		12.37	%		21.50	%		29.16	%		15.53	%
S&P/Citigroup Global ex-US Cap Range $500mm-$5bn		-2.73	%		15.98	%		22.20	%		29.82	%		16.34	%
MSCI EAFE Index		-1.75	%		11.17	%		16.83	%		21.59	%		8.28	%
Lipper Int'l Small-Cap Funds Index		-4.89	%		9.90	%		20.32	%		28.46	%		13.87	%
Columbia Acorn USA (LAUAX) (10/16/00)		-3.30	%		3.18	%		7.87	%		17.13	%		12.10	%
Russell 2000		-4.58	%		-1.57	%		6.80	%		16.25	%		8.04	%
Lipper Small-Cap Core Funds Index		-4.23	%		1.92	%		7.62	%		15.76	%		8.81	%
S&P 500		-3.33	%		5.49	%		8.62	%		12.83	%		2.67	%
Columbia Acorn Int'l Select (LAFAX) (10/16/00)		0.74	%		21.50	%		24.07	%		27.24	%		9.62	%
S&P/Citigroup World ex-US Cap Range $2-10B		-4.33	%		9.84	%		19.13	%		25.94	%		13.61	%
MSCI EAFE Index		-1.75	%		11.17	%		16.83	%		21.59	%		8.28	%
Lipper International Funds Index		-1.00	%		14.25	%		18.49	%		21.82	%		9.15	%
Columbia Acorn Select (LTFAX) (10/16/00)		-5.34	%		8.92	%		12.92	%		17.19	%		12.39	%
S&P MidCap 400		-2.73	%		7.98	%		10.27	%		16.20	%		8.98	%
Lipper Mid-Cap Growth Index		-0.03	%		21.41	%		13.88	%		17.93	%		1.41	%
S&P 500		-3.33	%		5.49	%		8.62	%		12.83	%		2.67	%
Columbia Thermostat Fund (CTFAX) (3/3/03)†		0.26	%		8.19	%		7.98	%		NA			11.43	%
S&P 500		-3.33	%		5.49	%		8.62	%		NA			14.27	%
Lehman Brothers U.S. Credit Intermediate Bond Index		2.17	%		5.60	%		3.83	%		NA			4.20	%
Lipper Flexible Portfolio Funds Index		-0.21	%		9.57	%		9.53	%		NA			13.17	%

*Not annualized.

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in a Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance changes over time. Please visit columbiafunds.com for daily and most recent month-end updates.

Performance results reflect any waivers or reimbursement of Fund expenses by the investment adviser and/or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results would have been lower.

Annual operating expense ratios are as stated in each Fund's current prospectus and differences in expense ratios disclosed elsewhere in this report may result from including fee waivers and reimbursements as well as different time periods used in calculating the ratios. Columbia Acorn Fund: Class A: 1.05%; Class B: 1.63%; Class C: 1.84%. Columbia Acorn International: Class A: 1.27%; Class B: 1.86%; Class C: 2.05%. Columbia Acorn USA: Class A: 1.30%; Class B: 1.89%; Class C: 2.09%. Columbia Acorn International Select: Class A: 1.63%; Class B: 2.23%; Class C:2.42%. Columbia Acorn Select: Class A: 1.27%; Class B: 1.88%; Class C: 2.08%. Columbia Thermostat Fund has a contractual expense waiver or reimbursement that expires April 30, 2008. Expense ratios without and with the contr actual waiver, including fees and expenses associated with the Fund's investments in other investment companies are: Class A: 1.35%, 1.19%; Class B: 1.88%, 1.69%; Class C: 2.15%, 1.94%, respectively.

†A "fund of funds" bears its allocable share of the costs and expenses of the underlying funds in which it invests. Such funds are thus subject to two levels of fees and potentially higher expense ratios than would be associated with an investment in an investment fund that invests and trades directly in financial instruments under the direction of a single manager.

All results shown assume reinvestment of distributions and do not reflect the deduction of taxes that a shareholder would pay on fund distributions or the redemption of fund shares.

All indexes are unmanaged. It is not possible to invest directly in an index. For index definitions, see Page 1 of this report.

3

Squirrel Chatter II: Ponzi Schemes and Politicians' Dreams

Each December I attend The University of Chicago Business Forecast luncheon. Typically the event features economic forecasts by two economists, plus a summary of world political and economic issues provided by Professor Marvin Zonis.¹ At this year's luncheon Professor Zonis stated that the U.S. Government had $50 trillion of unfunded liabilities. That's a staggering figure! Could it really be correct?

"Trust Me" Trust Funds

I've found that there is no precise U.S. Government unfunded liability number, though there are estimates. The U.S. Government Accountability Office (GAO) notes material weaknesses in federal government accounting in general, but has expressed an unqualified opinion on its 2007 Statement of Social Insurance. Any calculation of unfunded liabilities requires numerous actuarial assumptions plus a time horizon. The calculations by various government agencies cover liabilities for 75 years into the future.

However, it does appear that Professor Zonis' $50 trillion estimate was wrong. That number is now too low. On December 17, 2007, the GAO estimated that the U.S. Government's total reported liabilities, net social insurance commitments, and other fiscal exposures were approximately $53 trillion.² With apologies to the late Senator Everett Dirksen (Republican: Illinois), it seems that a trillion here and a trillion there adds up.³

Despite well-publicized concerns about Social Security, Medicare is in worse shape. Created in the 1930s, Social Security seems to have been a warm-up for bigger unfunded liabilities later on. Social Security is better funded, as Social Security tax rates are higher than Medicare tax rates. Medicare was signed into law in 1965 and spending for the program quickly ran out of control. The original cost estimate for Medicare hospital insurance in 1990, for example, was $9 billion; the actual cost that year hit $67 billion!⁴ According to the GAO, Medicare alone has over $36 trillion of unfunded liabilities.

But what of the Social Security and Medicare Trust Funds, the Funds that politicians promised to put in a "lock box?" It turns out the politicians spent the money elsewhere and the Trust Funds loaned their money to the U.S. Treasury by buying government bonds. The Trust Funds have no true third-party assets, but simply have promises from the U.S. Treasury to pay in the future. In order for the payments to be made the Treasury will have to raise taxes, cut other spending, borrow or print money.

What was the latest change that politicians made concerning unfunded liabilities? They increased them by adding prescription drugs to Medicare's benefits. This addition is noteworthy for three reasons. First, little new funding was created; enrollee premiums cover only about 25% of costs. Second, the program's costs and benefits are highly skewed. Baby boomers will have a net benefit of about $20,000 each while younger workers and future generations will have net costs of between $2,500 and $4,200 each.⁵ Third, when the new benefits were fully implemented in 2006, they drove a 19% increase in Medicare costs, the largest increase in decades. Over $10 trillion of Medicare's unfunded liability is from the drug program.

What are this year's presidential candidates saying about the unfunded liability problem? Virtually nothing and, even though taxpayers cannot afford Social Security, Medicare and other existing programs, some candidates are touting new proposals that substantially broaden federal health care spending. These plans include additional entitlements and mandatory, subsidized, health insurance participation. Cost estimates are dubious but range from $50 to $120 billion yearly.

Given the huge existing liabilities and proposals for additional benefits, it appears that the U.S. Government is operating an enormous Ponzi Scheme.⁶ Initial participants benefit but most taxpayers are likely to lose.

Large Liabilities and Possible Solutions

$53 trillion is a huge number, nearly four times all the goods and services produced in the United States in 2007. Currently Social Security is running a yearly surplus while Medicare is running a deficit. But the aging of baby boomers is driving yearly Medicare and Social Security spending higher, so the programs' cash needs will become very large in the next decade. Medicare deficits are projected to consume 25% of all federal income taxes by 2020. By 2050, Social Security, Medicare, and Medicaid will grow from 9% to 18% of GDP. This contrasts to total federal spending averaging about 20% of GDP over the last 50 years.⁷

Some of the richest people in America say their taxes are too low. What if they were taxed at 100%? Not 100% of income but 100% of their net worth! This "Che Guevara lite" (confiscation without murder) solution, if applied to the 2007 Forbes list of the richest

4

400 Americans, would yield a one-time receipt of $1.54 trillion. That would cover 2.9% of the problem, but is of course not a real solution as it would destroy capitalism.

How about raising tax rates on all of us? The Laffer Curve⁸ exists—there is an income tax rate that will yield the highest dollar amount of taxes, and that rate appears to be well under 100%. Even famed British economist John Maynard Keynes said that reducing too-high tax rates results in higher tax revenues. Very high tax rates choke economic activity and spur taxpayers to take legal and illegal measures to reduce payments.

Since federal income taxes began in 1913, there have been three rounds of major income tax rate cuts in the United States, and each resulted in faster economic growth and, ultimately, higher taxes collected. Paradoxically, though the rate cuts provided those with higher incomes the largest benefits, higher income people ended up paying greater percentages of total tax collections. A number of countries, including former Soviet republics, have adopted low, flat income tax rates and have seen economic growth surge and tax receipts increase.

No one knows what income tax rates create the highest tax revenues over the long run. In the last 50 years, the highest marginal tax rates in the United States have varied from a pre-Kennedy rate cut peak of 91% to a post-Reagan rate cut trough of 28%. Surprisingly, total federal government revenues as a percentage of GDP during that period have varied modestly, from 16.1% to 20.9%. Fiscal 2007 revenues were a bit above the midpoint, at 18.8% of GDP.⁹

While somewhat higher tax rates would probably increase near-term tax revenues, it is unlikely that substantially higher income tax rates alone can boost government receipts to the 30% or so of GDP eventually needed to fully fund the promised benefits. Massive value added taxes or sales taxes would likely be needed to provide tax revenue percentages that high. But huge tax hikes of any sort are likely to hurt economic growth, and additional solutions are needed.

As substantial liabilities become due in the next decade, there is an increased likelihood that voters will elect more courageous politicians that will strive to control spending and enact needed reforms. Perhaps the best single reform would be to restore more free market elements to our health care system. There needs to be more price transparency plus incentives for individuals and health care providers to control spending. Streamlined drug approval processes and additional tort reform would also help.

Incentives for innovation, rather than arbitrary price controls, are crucial. Improved technology has enabled over a 99.99% reduction in the cost of genome mapping in the last seven years. As costs continue to drop and advances continue to be made in biotechnology and pharmaceuticals, new ways to diagnose, treat and cure diseases are likely. Treatments customized to genetic factors promise to be much more effective and result in fewer side effects than many current drugs. The Columbia Acorn Funds have begun to own stocks in companies that are pursuing genetic tests, novel drugs and devices, plus information technology for better managing health care administration.

Outside the health care sector, Professor Jeremy Siegel has suggested that a solution for America's savings and retirement crisis will be sales of American assets to foreigners, especially those from countries with higher savings rates and younger populations. Innovative small- and mid-cap companies appear particularly attractive to foreigners, especially now that the dollar has weakened. The sale has begun, as mentioned in Columbia Acorn Fund's nutshell discussion on Page 8.

Charles P. McQuaid

President and Chief Investment Officer
Columbia Wanger Asset Management, L.P.

Opinions expressed in "Squirrel Chatter II" are those of the author and are not necessarily those of Columbia Wanger Asset Management, its parent organizations, or the Columbia Acorn Trust Board.

¹  Marvin Zonis is a professor emeritus at the Graduate School of Business at The University of Chicago, where he teaches courses on International Political Economy, Leadership and Business Strategy in the Era of E-Commerce.

²  Estimates by the Congressional Budget Office, Medicare trustees, and some private sources are higher.

³  Dirksen has been quoted as saying, "A billion here and a billion there, and pretty soon you're talking real money," but the Dirksen Congressional Center has been unable to verify the statement.

⁴  Source: American Enterprise Institute for Public Policy Research website, www.aei.org, "Medicare Prescription Drugs: Medical Necessity Meets Fiscal Insanity," by Joseph Antos and Jagadeesh Gokhale. Posted February 17, 2005.

⁵  Ibid.

⁶  In the 1920's, Charles Ponzi enticed investors with a bogus investment opportunity that promised a 40% return on their investment in just 90 days. Early investors were paid with dollars from later investors but most lost their money. Ponzi served four years in prison for this fraud, and then proceeded to promote other dubious ventures. He died in a charity ward of a Rio de Janeiro hospital in 1949.

⁷  Included in testimony on the future of Social Security presented by the Concord Coalition (www.concordcoalition.org) to a Senate special committee on aging, February 3, 2005.

⁸  The Laffer Curve is used to illustrate the concept of taxable income elasticity, the idea that government can maximize tax revenue by setting tax rates at an optimum point and that neither a 0% tax rate nor a 100% tax rate will generate government revenue. The curve was popularized by U.S. economics professor Arthur Laffer (b. 1940).

⁹  Source: Congressional Budget Office.

5

Understanding Your Expenses

As a Fund shareholder, you incur two types of costs. There are transaction costs, which generally include sales charges on purchases and may include redemption or exchange fees. There are also ongoing costs, which generally include investment advisory fees, Rule 12b-1 fees (distribution and service fees) and other Fund expenses. The following information is intended to help you understand your ongoing costs of investing in the Columbia Acorn Funds and to compare these costs with the ongoing costs of investing in other mutual funds.

Analyzing Your Fund's Expenses

To illustrate these ongoing costs, we have provided examples and calculated the expenses paid by investors in the Class A, B and C shares of the Columbia Acorn Funds for the last six months. The information in the table is based on an initial investment of $1,000.00, which is invested at the beginning of the reporting period and held for the entire period. Expense information is calculated two ways and each method provides you with different information. The amount listed in the "Actual" column is calculated using each Fund's actual operating expenses and total return for the period. The amount listed in the "Hypothetical" column assumes that the return each year is 5% before expenses and then applies each Fund's actual expense ratio for the period to the hypothetical return. You should not use the hypothetical account values and expenses to estimate either your actual account balance at the end of the period or the expenses you paid during the reporting period. See the "Compare With Other Funds" information for details on using the hypothetical data.

Compare With Other Funds

Since all mutual funds are required to include the same hypothetical calculations about expenses in shareholder reports, you can use this information to compare the ongoing cost of investing in the Funds with other funds. To do so, compare the 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of other funds. As you compare hypothetical examples of other funds, it is important to note that hypothetical examples are meant to highlight the continuing costs of investing in a fund and do not reflect any transaction costs, such as sales charges, or redemption or exchange fees.

Estimating Your Actual Expenses

To estimate the expenses that you actually paid over the period, first you will need your account balance at the end of the period:

•  For shareholders who receive their account statements from Columbia Management Services, Inc., your account balance is available online at columbiafunds.com or by calling Shareholder Services at (800) 922-6769.

•  For shareholders who receive their account statements from their brokerage firm, contact your brokerage firm to obtain your account balance.

1.  Divide your ending account balance by $1,000.00. For example, if an account balance was $8,600.00 at the end of the period, the result would be 8.6.

2.  In the section of the table titled "Expenses paid during the period," locate the amount for your Fund. You will find this number is in the column labeled "Actual." Multiply this number by the result from step 1. Your answer is an estimate of the expenses you paid on your account during the period.

6

July 1, 2007 – December 31, 2007

	Account value at the beginning of the period ($)				Account value at the end of the period ($)				Expenses paid during the period ($)				Fund's annualized expense ratio (%)*
	Actual		Hypothetical		Actual		Hypothetical		Actual		Hypothetical		Actual
Columbia Acorn Fund
Class A		1,000.00		1,000.00		964.21		1,020.01		5.10		5.24		1.03
Class B		1,000.00		1,000.00		961.39		1,017.19		7.86		8.08		1.59
Class C		1,000.00		1,000.00		960.58		1,016.18		8.85		9.10		1.79
Columbia Acorn International
Class A		1,000.00		1,000.00		1,021.68		1,018.85		6.42		6.41		1.26
Class B		1,000.00		1,000.00		1,019.00		1,016.03		9.26		9.25		1.82
Class C		1,000.00		1,000.00		1,017.69		1,015.02		10.27		10.26		2.02
Columbia Acorn USA
Class A		1,000.00		1,000.00		943.49		1,018.90		6.12		6.36		1.25
Class B		1,000.00		1,000.00		940.52		1,015.98		8.95		9.30		1.83
Class C		1,000.00		1,000.00		940.01		1,015.02		9.88		10.26		2.02
Columbia Acorn International Select
Class A		1,000.00		1,000.00		1,088.52		1,017.64		7.90		7.63		1.50
Class B		1,000.00		1,000.00		1,084.79		1,014.57		11.09		10.71		2.11
Class C		1,000.00		1,000.00		1,084.29		1,013.61		12.08		11.67		2.30
Columbia Acorn Select
Class A		1,000.00		1,000.00		933.91		1,019.21		5.80		6.06		1.19
Class B		1,000.00		1,000.00		930.79		1,016.28		8.61		9.00		1.77
Class C		1,000.00		1,000.00		929.88		1,015.27		9.58		10.01		1.97
Columbia Thermostat Fund
Class A		1,000.00		1,000.00		1,037.81		1,022.68		2.57		2.55		0.50
Class B		1,000.00		1,000.00		1,034.99		1,020.16		5.13		5.09		1.00
Class C		1,000.00		1,000.00		1,033.22		1,018.90		6.41		6.36		1.25

Expenses paid during the period are equal to each Fund's annualized expense ratio, multiplied by the average account value over the period and then multiplied by the number of days in the Fund's most recent fiscal half-year and divided by 365.

Had the investment adviser and/or any of its affiliates not waived fees or reimbursed a portion of expenses, account value at the end of the period would have been reduced.

It is important to note that the expense amounts shown in the table are meant to highlight only ongoing costs of investing in the Funds and do not reflect any transaction costs, such as sales charges, redemption or exchange fees. Therefore, the hypothetical examples provided may not help you determine the relative total costs of owning different funds. If these transaction costs were included, your costs would have been higher.

Columbia Thermostat Fund's expenses do not include fees and expenses incurred by the Fund from the underlying portfolio funds in which it invests.

*For the six months ended December 31, 2007.

7

Columbia Acorn Fund

In a Nutshell

Charles P. McQuaid

Lead Portfolio Manager

Robert A. Mohn

Co-Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Please visit columbiafunds.com for daily and most recent month-end performance updates.

Fund's Positions

in Mentioned Holdings

as of 12/31/07

FMC Technologies	1.6	%
Fugro	1.5	%
Coach	1.1	%
Ultra Petroleum	1.0	%
Atwood Oceanics	0.6	%
Southwestern Energy	0.5	%
Housing Development Finance	0.5	%
Hong Kong Exchanges and Clearing	0.5	%
AmeriCredit	0.5	%
NAVTEQ	0.5	%
Genlyte Group	0.5	%
Chico's FAS	0.3	%
MGI Pharma	0.2	%

Portfolio holdings are subject to change periodically and may not be representative of current characteristics and holdings.

Columbia Acorn Fund returned 7.39% (Class A shares, without sales charge) in 2007, substantially beating the 1.38% return of its primary benchmark, the Russell 2500 Index. The Fund also outperformed the large-cap S&P 500's gain of 5.49%, which was gratifying as small caps tended to underperform large caps during the period.

The equity markets were poor in the fourth quarter; both volatile and down. Columbia Acorn Fund dropped 3.30% in the quarter, falling less than the small-cap benchmarks and essentially in line with the mid- and large-cap benchmarks.

Energy stocks helped performance substantially during the year and somewhat during the quarter. Wellhead maker FMC Technologies was the Fund's largest dollar winner in 2007. It provided a blowout 84% gain as earnings grew rapidly. Dutch oilfield service provider Fugro sounded out a 63% profit. A third company benefiting from the pursuit of offshore oil, Atwood Oceanics, surged more than 104% in the year and 31% in the fourth quarter. Several oil and gas producers were also hot. Southwestern Energy jumped 59% in the year and 33% in the quarter, while Ultra Petroleum appreciated 50% and 15%, respectively. We thank our energy analyst Bill Doyle for these picks.

Columbia Acorn Fund had a record 39 takeovers of portfolio companies announced in 2007, including six in the fourth quarter. Kronos, a labor management software developer, booked the largest dollar gain among takeovers during the year, rising 50%. Two takeovers that were announced during the fourth quarter were also big winners for the year. Map data provider NAVTEQ climbed 114% in 2007; it agreed to be bought by Finland's Nokia. Specialty pharmaceutical producer MGI Pharma announced a sellout to Japan's Eisai, and provided a healthy gain of more than 116%. Also in the fourth quarter, lighting fixtures maker Genlyte Group agreed to sell to Holland's Philips Electronics. It brightened our results as the Fund's largest dollar winner in the quarter, showing a 47% profit. While sellouts to private equity slowed in late 2007, sellouts to foreign companies continued.

Foreign stocks were up 26.17%* during the year, but were off 3.03% during the quarter. Hong Kong Exchanges and Clearing rose over 160% in 2007, and provided the Fund's second largest dollar gains. Fugro, mentioned above, was the Fund's third largest dollar winner. India's Housing Development Finance benefited from that country's economic growth and jumped 98%. We trimmed Columbia Acorn Fund's foreign holdings to 11.6% of assets at year-end.

Consumer stocks hurt. Chico's FAS fell 57% in the year and 36% in the quarter, largely on fashion missteps. Coach executed splendidly, but ended the year off 29% as it fell 35% in the quarter due to macroeconomic concerns. Finance company AmeriCredit lost 49% in the year and 27% in the quarter as investors worried about used car loans and sources of funding.

We are pleased that our stock picking rebounded strongly in 2007 after a mildly disappointing 2006. The early 2008 market turmoil feels disconcerting, but may provide favorable purchasing opportunities.

*This return is not comparable to mutual fund returns, as it is gross of fees and other expenses and does not portray the cash effects incurred by actual mutual funds. Columbia Acorn Fund's foreign stockholdings were heavily weighted toward energy during the periods covered and were not purchased as a balanced, stand-alone portfolio.

Small- and mid-cap stocks are often more volatile and less liquid than the stocks of larger companies. Small companies may have a shorter history of operations than larger companies and may have a less diversified product line, making them more susceptible to market pressure. International investments involve greater potential risks, including less regulation, currency fluctuations, economic instability and political developments.

8

Columbia Acorn Fund (LACAX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through December 31, 2007

Inception 10/16/00		1 year	5 years	Life of fund
Returns before taxes	NAV POP	7.39% 1.22	19.37% 17.96	12.69% 11.77
Returns after taxes on distributions	NAV POP	6.19 0.09	18.48 17.08	11.68 10.77
Returns after taxes on distributions and sale of fund shares	NAV POP	6.43 2.32	17.09 15.80	10.94 10.10
Russell 2500 (pretax)		1.38	16.99	9.18
S&P 500 (pretax)		5.49	12.83	2.67

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.< /p>

Public offering price (POP) returns include the maximum sales charge of 5.75% for Class A shares. Net asset value (NAV) returns do not include sales charges or contingent deferred sales charges (CDSC).

The Fund's Class A shares annual operating expense ratio, as stated in the current prospectus, is 1.05%.

Columbia Acorn Fund Portfolio Diversification

as a % of net assets as of 12/31/07

Columbia Acorn Fund Top 10 Holdings

as a % of net assets as of 12/31/07

1.	FMC Technologies Oil & Gas Wellhead Manufacturer	1.6%
2.	Fugro (Netherlands) Oilfield Services	1.5%
3.	Abercrombie & Fitch Teen Apparel Retailer	1.3%
4.	Expeditors International of Washington International Freight Forwarder	1.2%
5.	Ametek Aerospace/Industrial Instruments	1.2%
6.	Coach Designer & Retailer of Branded Leather Accessories	1.1%
7.	Eaton Vance Specialty Mutual Funds	1.1%
8.	People's United Connecticut Savings & Loan	1.0%
9.	SEI Investments Mutual Fund Administration & Investment Management	1.0%
10.	Donaldson Industrial Air Filtration	1.0%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $75,000 Investment in Columbia Acorn Fund (Class A)

October 16, 2000 through December 31, 2007

Illustration is based on a hypothetical $75,000 investment from inception in Class A shares of the Fund, which includes a 4.50% maximum initial sales charge for this level of investment. The index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $19.9 billion

9

Columbia Acorn International

In a Nutshell

P. Zachary Egan

Co-Portfolio Manager

Louis J. Mendes III

Co-Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Please visit columbiafunds.com for daily and most recent month-end performance updates.

Fund's Positions

in Mentioned Holdings

as of 12/31/07

Atwood Oceanics	1.3	%
Hong Kong Exchanges and Clearing	1.2	%
Smit Internationale	1.2	%
Singapore Exchange	1.1	%
Taewoong	0.5	%
Sung Kwang Bend	0.5	%

Portfolio holdings are subject to change periodically and may not be representative of current characteristics and holdings.

Columbia Acorn International gained 16.90% (Class A shares, without sales charge) in 2007, 4.53% ahead of the S&P/Citigroup EMI Global ex-US Index ("EMI") and 5.73% ahead of the large-cap MSCI EAFE Index ("EAFE"). During the fourth quarter, the Fund fell 2.10%, while the EMI declined by 3.36%. The Fund's results for the year were driven most notably by strong underlying performance in continental Europe and in the emerging markets, which more than offset declining markets in Japan and the United Kingdom. On a sector basis, energy and financial stocks all posted strong absolute and relative performance in the Fund. Finally, the weak performance of the U.S. dollar translated into a net gain of 6.7% for our shareholders.

For the eighth consecutive year, international small-cap stocks, as measured by the EMI Index, have outperformed international large-cap stocks, as measured by the EAFE Index. Strong underlying growth in China, India and several other large emerging economies drove global demand for energy, raw materials and industrial goods for yet another year. Many of the Fund's industrial exporters reported record profitability as pricing power and capacity utilization remained high. For example, Sung Kwang Bend and Taewoong, two Korean industrial companies involved in global energy infrastructure projects, rose 273% and 172%, respectively. Export activity kept Asian and European ports busy. Smit Internationale, a Dutch operator of tugboats and salvage vessels, rose 98% on strong demand for its services as seaborne trade continues to grow at a considerably higher rate than global GDP.

During the year, the only significant change in average regional exposure within the portfolio was an increase in Asia ex-Japan investments from 8% to 13% of the Fund's equity, funded primarily by a reduction in the United Kingdom and Ireland from 16% to 11%. This reallocation of assets had a favorable impact on the Fund. Our UK/Ireland positions averaged a mid-single digit negative return while those in Asia ex-Japan returned over 60%, representing both the best and worst performing regional returns. This can be explained in large part by the subprime crisis in the United Kingdom, which had broad repercussions across the market. While in Asia ex-Japan, robust economic development drove high volumes on the companies that operate the regional equity and derivative exchanges, in which the Fund held sizable positions. Hong Kong Exchanges and Clearing and Singapore Exchange appreciated more than 160% and 152%, respectively, in the y ear.

At the sector level, the Fund's ongoing overweight in energy services companies was helpful. Energy prices remained near record levels, underpinning solid earnings growth in oil services companies, as they expand to meet growing demand from the large oil conglomerates. The Fund's energy stocks, representing 7.6% of equity, generated over a 50% return to shareholders. Outstanding stocks included Atwood Oceanics, a provider of offshore drilling rigs, which increased more than 104% in 2007.

As we look ahead to 2008, the impact of the continuing crisis in subprime mortgages in the United States and United Kingdom on global markets remains a looming concern. While many portfolio companies continue to report excellent business fundamentals, as we write this in mid-January the markets appear to be taking into consideration the distinct possibility of a U.S. and European recession. We expect volatility to remain high. As long-term, fundamental investors, we will work to take advantage of the pricing anomalies this will likely create.

Thank you for your continued investment in Columbia Acorn International.

International investments involve greater potential risks, including less or different regulation, currency fluctuations, economic instability and political developments. Investments in small- and mid-cap companies may be subject to greater volatility and price fluctuations because they may be thinly traded and less liquid. Investing in emerging markets may involve greater risks than investing in more developed countries.

10

Columbia Acorn International (LAIAX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through December 31, 2007

Inception 10/16/00		1 year	5 years	Life of fund
Returns before taxes	NAV POP	16.90% 10.17	29.25% 27.73	11.88% 10.97
Returns after taxes on distributions	NAV POP	15.72 9.06	28.50 26.98	10.97 10.07
Returns after taxes on distributions and sale of fund shares	NAV POP	12.82 8.35	26.32 24.90	10.25 9.42
S&P/Citigroup EMI Global ex-US (pretax)		12.37	29.16	15.53
S&P/Citigroup Global ex-US Cap Range $500mm-$5bn (pretax)		15.98	29.82	16.34

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.< /p>

Public offering price (POP) returns include the maximum sales charge of 5.75% for Class A shares. Net asset value (NAV) returns do not include sales charges or contingent deferred sales charges (CDSC).

The Fund's Class A shares annual operating expense ratio, as stated in the current prospectus, is 1.27%.

Columbia Acorn International Portfolio Diversification

as a % of net assets as of 12/31/07

Columbia Acorn International Top 10 Holdings

as a % of net assets as of 12/31/07

1.	Fugro (Netherlands) Oilfield Services	1.9%
2.	Hexagon (Sweden) Measurement Equipment & Polymers	1.4%
3.	SES Global (France) Satellite Broadcasting Services	1.4%
4.	Intralot (Greece) Lottery & Gaming Systems & Services	1.3%
5.	Atwood Oceanics (United States) Offshore Drilling Contractor	1.3%
6.	Housing Development Finance (India) Indian Mortgage Lender	1.2%
7.	Hong Kong Exchanges and Clearing (Hong Kong) Hong Kong Equity & Derivatives Market Operator	1.2%
8.	Smit Internationale (Netherlands) Harbor & Offshore Towage & Marine Services	1.2%
9.	Suzano (Brazil) Brazilian Pulp & Paper Producer	1.2%
10.	ShawCor (Canada) Oil & Gas Pipeline Products	1.1%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn International (Class A)

October 16, 2000 through December 31, 2007

Illustration is based on a hypothetical $10,000 investment from inception in Class A shares of the Fund, which includes a 5.75% maximum initial sales charge. The indexes are unmanaged and returns for both the indexes and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $5.7 billion

11

Columbia Acorn USA

In a Nutshell

Robert A. Mohn

Lead Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Please visit columbiafunds.com for daily and most recent month-end performance updates.

Fund's Positions

in Mentioned Holdings

as of 12/31/07

FMC Technologies	2.9	%
Atwood Oceanics	2.1	%
Quicksilver Resources	2.0	%
ITT Educational Services	2.0	%
Flir Systems	1.7	%
BioMarin	1.6	%
True Religon Apparel	1.3	%
Tellabs	1.1	%
Oxford Industries	1.0	%
Urban Outfitters	0.9	%
AmeriCredit	0.9	%
World Acceptance	0.8	%
Coach	0.4	%

Portfolio holdings are subject to change periodically and may not be representative of current characteristics and holdings.

Columbia Acorn USA fell 3.30% (Class A shares, without sales charge) in the fourth quarter while its benchmark, the Russell 2000 Index, declined 4.58%. For the year ended December 31, 2007, the Fund posted a 3.18% gain, outperforming the Russell 2000, which fell 1.57% for the year, dragged down by the ailing housing and credit markets.

Energy stocks were our biggest winners for both the quarter and the year. Oil service company Atwood Oceanics, an owner of offshore drilling rigs, was up 31% in the quarter and more than 104% for the year. Atwood reported a 100% utilization rate for its rigs in the third quarter and has been able to demand very high day rates all year long. Natural gas and coal seam gas producer Quicksilver Resources gained 27% in the quarter and was up 63% for the year on strong production growth. While not a standout in the quarter, FMC Technologies was another annual winner with an 84% gain on gushing sales of its subsea wellhead and oil production systems.

Two mergers in the fourth quarter, and one from the first, brought in strong gains. Genlyte Group, a manufacturer of commercial lighting fixtures, gained 47% in the quarter (21% for the year). Pharmaceutical company MGI Pharma gained 44% on take-out news in the quarter and ended the year up more than 116%. In the first quarter, labor management software developer Kronos announced it was being sold. It was the Fund's largest position at that time. The stock was eliminated from the portfolio with a 50% annualized gain.

Other winners included Flir Systems, a manufacturer of infrared cameras. The company won several new defense department contracts during the year and posted a 13% gain in the quarter and 97% return for the year. BioMarin gained 42% in the quarter and ended the year up 99% after announcing that the FDA had approved its drug for treating a genetic disorder that affects approximately 20,000 people in the United States. By targeting rare disorders, BioMarin is able to charge higher prices and enjoy longer patent protection periods for its drugs.

While several of the Fund's retail holdings outperformed during the quarter's retail slump—True Religion Apparel gained 21% in the quarter and Urban Outfitters increased 25%—others did not. Oxford Industries fell along with the sales of its Tommy Bahama line, dropping 28% in the quarter and 47% for the year. Accessories retailer Coach also succumbed to the slump, falling 35% in the fourth quarter and 29% for the year.

ITT Educational Services ended the year up 28% but fell 30% in the fourth quarter as student loan financing began to freeze up. Telecom equipment provider Tellabs fell 31% in the quarter and was off 36% for the year on declining revenues. The company has been hurt by the consolidation of major telecommunication providers that, combined, need less equipment. Rounding out the laggards list were AmeriCredit, down 27% in the quarter and 49% for the year, and World Acceptance, off 18% in the quarter and 42% for the year. Both stocks were hurt by the credit market crunch.

After a rocky end to 2007, investors were hoping for better in 2008. But as of the writing of this report, the New Year is off to a poor start as fears of a U.S. recession grow. When tales of economic woe dominate the headlines, long-term investment opportunities tend to sprout. We continue our relentless search for small-cap, niche companies with the ability to exhibit strong business growth over the next three to five years (even while the sky appears to be falling).

Risks include stock market fluctuations due to economic and business developments. Investments in small- and mid-cap companies may be subject to greater volatility and price fluctuations because they may be thinly traded and less liquid.

12

Columbia Acorn USA (LAUAX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through December 31, 2007

Inception 10/16/00		1 year	5 years	Life of fund
Returns before taxes	NAV POP	3.18% -2.75	17.13% 15.75	12.10% 11.19
Returns after taxes on distributions	NAV POP	2.27 -3.61	16.66 15.28	11.76 10.84
Returns after taxes on distributions and sale of fund shares	NAV POP	3.30 -0.63	15.12 13.87	10.71 9.87
Russell 2000 (pretax)		-1.57	16.25	8.04

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.< /p>

Public offering price (POP) returns include the maximum sales charge of 5.75% for Class A shares. Net asset value (NAV) returns do not include sales charges or contingent deferred sales charges (CDSC).

The Fund's Class A shares annual operating expense ratio, as stated in the current prospectus, is 1.30%.

Columbia Acorn USA Portfolio Diversification

as a % of net assets as of 12/31/07

Columbia Acorn USA Top 10 Holdings

as a % of net assets as of 12/31/07

1.	FMC Technologies Oil & Gas Wellhead Manufacturer	2.9%
2.	Crown Castle International Communications Towers	2.7%
3.	Atwood Oceanics Offshore Drilling Contractor	2.1%
4.	Ametek Aerospace/Industrial Instruments	2.1%
5.	Abercrombie & Fitch Teen Apparel Retailer	2.0%
6.	Quicksilver Resources Natural Gas & Coal Seam Gas Producer	2.0%
7.	ITT Educational Services Post-secondary Degree Services	2.0%
8.	Time Warner Telecom Fiber Optic Telephone/Data Services	1.9%
9.	Flir Systems Infrared Cameras	1.7%
10.	ESCO Technologies Automatic Electric Meter Readers	1.7%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $75,000 Investment in Columbia Acorn USA (Class A)

October 16, 2000 through December 31, 2007

Illustration is based on a hypothetical $75,000 investment from inception in Class A shares of the Fund, which includes a 4.50% maximum initial sales charge for this level of investment. The index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $1.5 billion

13

Columbia Acorn International Select

In a Nutshell

Christopher J. Olson

Lead Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Please visit columbiafunds.com for daily and most recent month-end performance updates.

Fund's Positions

in Mentioned Holdings

as of 12/31/07

Nintendo	3.6	%
Potash Corp. of Saskatchewan	3.1	%
Diamond Offshore	3.1	%
Hong Kong Exchanges and Clearing	2.2	%
Ibiden	1.9	%
China Shipping Development	1.7	%
Atwood Oceanics	1.6	%
Uranium One	1.3	%
Singapore Exchange	1.2	%
Kenedix	1.0	%

Portfolio holdings are subject to change periodically and may not be representative of current characteristics and holdings.

Columbia Acorn International Select ended the fourth quarter and the year well ahead of its benchmark, the S&P/Citigroup World ex-US Cap Range $2-10B Index. In a rough fourth quarter for nearly all world markets, the Fund gained 0.74% (Class A shares, without sales charge) while the benchmark fell 4.33%. For the one-year period, the Fund increased 21.50%, more than doubling the 9.84% gain of the benchmark. As mentioned last quarter, our decision to sell out of banking stocks helped drive outperformance as the credit market turmoil that arose in the second half of the year rocked the financial sector.

Big winners in the quarter and the year included Japan's Nintendo. The stock was up 18% in the quarter and 148% for the year on strong demand for its Wii gaming console and associated video games. Potash Corp. of Saskatchewan was another big winner gaining 35% in the quarter and finishing the year up 201%. The company is the world's largest producer of potash and is benefiting from the positive impact higher agricultural prices are having on fertilizer prices. Contract drilling companies Atwood Oceanics and Diamond Offshore also posted strong gains in the quarter and year on strong demand for their services. Atwood gained 31% in the quarter and was up over 104% for the year while Diamond Offshore gained 27% in the fourth quarter and finished the year up 43%. Other big winners for the year included exchange operators Hong Kong Exchanges and Clearing, up more than 160%, and Singapore Exchange, up 152%. While Hong Kong Exchanges an d Clearing gave back some gains in the fourth quarter, both stocks benefited from very strong trading volumes throughout the year.

On the downside, new position Uranium One was off 29% for the annual period due to a setback in the startup of one of its uranium mines in Kazakhstan. China Shipping Development, China's dominant shipper of oil and coal, fell 19% in the quarter (but was up 3% for the year) due to global concerns about falling shipping rates. The company, however, has continued to report earnings upgrades due to shipping rate increases in China. Japan's Ibiden, a manufacturer of electronic parts and ceramics, fell 18% in the quarter on global recession worries, but the stock ended the year up 37%. Japanese real estate investment manager Kenedix had the largest 12-month dollar loss, falling 30% due to rising interest rates in Japan and concerns that real estate will suffer. Irish beverage company C&C Group fell 19% in the Fund before we sold it. Company earnings and sales declined due to increased competition and poor summer weather.

Global equity markets are entering an interesting and potentially volatile period as the United States works through its significant financial problems and enters what appears to be a much slower period of economic growth. We believe that this will impact economies and companies around the world. While this may mean additional risks for investors, we believe it may also give us additional opportunities to pick up some very good companies at compelling prices.

International investments involve greater potential risks, including less or different regulation, currency fluctuations, economic instability and political developments. Investments in small- and mid-cap companies may be subject to greater volatility and price fluctuations because they may be thinly traded and less liquid. Investing in emerging markets may involve greater risks than investing in more developed countries.

14

Columbia Acorn International Select (LAFAX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through December 31, 2007

Inception 10/16/00		1 year	5 years	Life of fund
Returns before taxes	NAV POP	21.50% 14.51	27.24% 25.74	9.62% 8.73
Returns after taxes on distributions	NAV POP	20.54 13.60	27.09 25.60	9.51 8.62
Returns after taxes on distributions and sale of fund shares	NAV POP	15.40 10.78	24.55 23.16	8.53 7.72
S&P/Citigroup World ex-US Cap Range $2-10B (pretax)		9.84	25.94	13.61

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.< /p>

Public offering price (POP) returns include the maximum sales charge of 5.75% for Class A shares. Net asset value (NAV) returns do not include sales charges or contingent deferred sales charges (CDSC).

The Fund's Class A shares annual operating expense ratio, as stated in the current prospectus, is 1.63%.

Columbia Acorn International Select Portfolio Diversification

as a % of net assets as of 12/31/07

Columbia Acorn International Select Top 10 Holdings

as a % of net assets as of 12/31/07

1.	Fugro (Netherlands) Oilfield Services	4.7%
2.	Nintendo (Japan) Entertainment Software & Hardware	3.6%
3.	SES Global (France) Satellite Broadcasting Services	3.5%
4.	Potash Corp. of Saskatchewan (Canada) World's Largest Producer of Potash	3.1%
5.	Diamond Offshore (United States) Contract Driller	3.1%
6.	Hexagon (Sweden) Measurement Equipment & Polymers	2.9%
7.	Lenovo Group (China) Third Largest PC Vendor Globally	2.7%
8.	Sino Gold (Australia) Gold Mining in The People's Republic of China	2.7%
9.	Smith & Nephew (United Kingdom) Medical Equipment & Supplies	2.7%
10.	Impala Platinum Holdings (South Africa) Platinum Group Metals Mining & Refining	2.7%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn International Select (Class A)

October 16, 2000 through December 31, 2007

Illustration is based on a hypothetical $10,000 investment from inception in Class A shares of the Fund, which includes a 5.75% maximum initial sales charge. The index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $277.0 million

15

Columbia Acorn Select

In a Nutshell

Ben Andrews

Lead Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end performance updates.

Fund's Positions

in Mentioned Holdings

as of 12/31/07

Cardtronics	0.7	%
Knoll	0.7	%
American Reprographics	0.5	%
VisionChina Media	0.5	%
Bovespa	0.4	%

Portfolio holdings are subject to change periodically and may not be representative of current characteristics and holdings.

Columbia Acorn Select declined 5.34% (Class A shares, without sales charge) in the fourth quarter. This compares to approximately 3% declines for the S&P MidCap 400 and S&P 500 indexes during the quarter. In 2007, the Fund was up 8.92% vs. a gain of 7.98% for the S&P MidCap 400 and a 5.49% increase for the S&P 500. I am pleased that the Fund beat its benchmark for the year.

At the writing of this commentary, we have entered the first quarter of 2008 and many believe the United States has already slipped into a recession. As we look back on the carnage that concluded by the end of the second week in January, a lot of small- and mid-cap stocks have already lost 40% of their value in the last six months. We may be early on in the recession (time wise) but the destruction of capital has already been significant. Therefore, I believe the market may already reflect a large amount of the capital losses that we'll see with this current recession. I put a handful of what I believe to be turnaround candidates in the portfolio in the first half of 2007. These stocks were fairly washed out upon purchase and were taking steps that I believed would improve their fundamentals. In theory, the return to growth for these companies should be counter cyclical to the U.S. economy's woes. So far their improvements have not been meaningful and their shares have continued to decline. This was not the idea but in reviewing these positions, I am more excited by the changes taking place at these companies now than I was when I bought them. If this pattern of improvement can continue, which I believe it will, then these stocks could give us the desired effect in a sluggish economic environment. If not, the holdings may be replaced.

During the fourth quarter, we added five new names while removing one. We exited the Fund's position in Liberty Global during the quarter due to its increased valuation and our concern that its European franchise will experience greater competition than we previously believed. The five added companies were Knoll, Bovespa, VisionChina Media, Cardtronics, and American Reprographics. We took advantage of market chaos at the end of the year to purchase two of these stocks in IPOs at lower than the initial offering price. The price for VisionChina was set at $11 but that didn't generate enough interest from nervous investors so we were able to reset the price with a bid of $8. Cardtronics was initially offered at $10 and instantly collapsed below the offering. The underwriter then spent all morning buying back stock in an attempt to defend the deal. Our traders went to them in the afternoon and bid $8⁵/₈ for 25% of the deal, thus eliminating the over supply of accounts that just wanted to flip the stock. We believe a purchase at this level may reward our shareholders over the coming quarters. VisionChina Media uses real-time mobile digital television broadcast to deliver content and advertising on mass transportation systems in China. Cardtronics owns and manages the largest fleet of ATM machines worldwide.

The subprime crisis allowed us to purchase a couple of companies at discounted prices that we believe won't be significantly damaged by the current market turmoil. They included office interiors and office furniture systems manufacturer Knoll and American Reprographics. American Reprographics is the largest provider of document management services to the architectural, engineering and construction industries and its stock had fallen 50% in the last six months of 2007. The fifth and final new name was Bovespa, the owner of the Sao Paulo stock exchange.

Risks include stock market fluctuations due to economic and business developments. The Fund also has potentially greater price volatility due to the Fund's concentration in a limited number of stocks of mid-size companies. The Fund is a non-diversified fund and may, therefore, have a greater risk of loss from a few issuers than a similar fund that invests more broadly. The Fund may not operate as a nondiversified fund at all times. International investments involve greater potential risks, including less regulation, currency fluctuations, economic instability and political developments.

16

Columbia Acorn Select (LTFAX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through December 31, 2007

Inception 10/16/00		1 year	5 years	Life of fund
Returns before taxes	NAV POP	8.92% 2.66	17.19% 15.81	12.39% 11.47
Returns after taxes on distributions	NAV POP	8.55 2.31	16.84 15.46	12.11 11.19
Returns after taxes on distributions and sale of fund shares	NAV POP	6.29 2.19	15.14 13.88	10.94 10.09
S&P MidCap 400 (pretax)		7.98	16.20	8.98

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.< /p>

Public offering price (POP) returns include the maximum sales charge of 5.75% for Class A shares. Net asset value (NAV) returns do not include sales charges or contingent deferred sales charges (CDSC).

The Fund's Class A shares annual operating expense ratio, as stated in the current prospectus, is 1.27%.

Columbia Acorn Select Portfolio Diversification

as a % of net assets as of 12/31/07

Columbia Acorn Select Top 10 Holdings

as a % of net assets as of 12/31/07

1.	Potash Corp. of Saskatchewan (Canada) World's Largest Producer of Potash	6.4%
2.	Uranium One (South Africa) Uranium Mines in South Africa, Kazakhstan, Australia & the U.S.	5.2%
3.	Janus Capital Group Manages Mutual Funds	4.4%
4.	Abercrombie & Fitch Teen Apparel Retailer	4.3%
5.	Conseco Life, Long-term Care & Medical Supplement Insurance	3.9%
6.	Safeway Supermarkets	3.9%
7.	Expedia Online Travel Services Company	3.6%
8.	Tellabs Telecommunications Equipment	3.6%
9.	ITT Educational Services Post-secondary Degree Services	3.6%
10.	American Tower Communications Towers in USA & Mexico	3.2%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $100,000 Investment in Columbia Acorn Select (Class A)

October 16, 2000 through December 31, 2007

Illustration is based on a hypothetical $100,000 investment from inception in Class A shares of the Fund, which includes a 4.50% maximum initial sales charge for this level of investment. The index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $3.0 billion

17

Columbia Thermostat Fund

In a Nutshell

Charles P. McQuaid

Lead Portfolio Manager

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Performance may reflect any voluntary waivers or reimbursements of fund expenses by the Adviser or its affiliates. Absent these waivers, or reimbursement arrangements, performance results may be lower. Visit columbiamanagement.com for daily and most recent month-end performance updates.

A "fund of fund" bears its allocable share of the costs and expenses of the underlying funds in which it invests. Such funds are thus subject to two levels of fees and potentially higher expense ratios than would be associated with a fund that invests and trades directly in financial instruments under the direction of a single manager.

Columbia Thermostat Fund ended the fourth quarter up 0.26% (Class A shares, without sales charge). This compares to a 3.33% drop in the S&P 500 Index and a 2.17% gain for the Lehman Brothers U.S. Credit Intermediate Bond Index. In 2007, Columbia Thermostat gained 8.19%, topping the S&P 500, up 5.49%, and the Lehman Brothers U.S. Credit Intermediate Bond Index, up 5.60%.

As the table illustrates, all of Columbia Thermostat's equity funds fell in the fourth quarter, resulting in a weighted loss of 2.86%. Bond returns softened the fall with a 1.68% gain. For the year, equities returned 9.22% while the bond component posted a 4.57% return.

Two changes were made to the Fund. Effective December 27, Columbia Federal Securities Fund was replaced with Columbia U.S. Treasury Index Fund. This new fund provides a lower cost fixed income investment choice.

We also revised the Fund's S&P 500 allocation table. In order to better reflect corporate earnings growth, the change adds equity and reduces bond exposures. Because the Fund does not reverse reallocations within 31 days, the change was fortuitously delayed during a time of market weakness. The reallocation was implemented on January 14, 2008, when the Fund hiked stock positions to 60% from 35%.

The credit crunch and housing woes dealt a tough blow to the markets in late 2007. Recession worries have since grown, contributing to volatility. Columbia Thermostat Fund is designed to use these bumps in the market to its advantage, keeping a portion of your invested dollars at an even temperature.

Results of the Funds Owned in Columbia Thermostat Fund

at December 31, 2007

Equities Fund	Weightings in Category			4th quarter returns			1-year returns to 12/31/07
Columbia Acorn Fund Z		15	%		-3.22	%		7.69	%
Columbia Acorn Select Z		10	%		-5.24	%		9.20	%
Columbia Marsico Growth Fund		15	%		-0.47	%		14.19	%
Columbia Acorn International Z		15	%		-2.01	%		17.28	%
Columbia Dividend Income Fund		20	%		-2.99	%		6.94	%
Columbia Large Cap Enhanced Core Fund		25	%		-3.66	%		4.05	%
Weighted Average Equity Return/Loss					-2.86	%		9.22	%
Fixed Income Fund	Weightings in Category			4th quarter returns			1-year returns to 12/31/07
Columbia Intermediate Bond Fund		50	%		1.68	%		4.62	%
Columbia U.S. Treasury Index Fund*		30	%		3.93	%		8.78	%
Columbia Federal Securities Fund*		0	%		3.31	%		5.97	%
Columbia Conservative High Yield Fund		20	%		-0.69	%		2.35	%
Weighted Average Income Return					1.68	%		4.57	%

*Effective December 27, 2007, Columbia Federal Securities Fund was replaced with Columbia U.S. Treasury Index Fund. The weighted average income return reflects the performance of both funds for the period owned.

Columbia Thermostat Fund
Rebalancing in the Fourth Quarter

October 8, 2007:	25% stock, 75% bond
November 8, 2007:	35% stock, 65% bond
November 13, 2007:	40% stock, 60% bond
December 14, 2007:	35% stock, 65% bond

The value of an investment in the Fund is based primarily on the performance of the underlying portfolio funds and the allocation of the Fund's assets among them. An investment in the underlying funds may present certain risks, including stock market fluctuations that occur in response to economic and business developments; and a greater degree of social, political and economic volatility associated with international investing. Small- and mid-cap stocks are often more volatile and less liquid than the stocks of larger companies. Small companies may have a shorter history of operations than larger companies and may have a less diversified product line, making them more susceptible to market pressure. International investments involve greater potential risks, including less or different regulation, currency fluctuations, economic instability and political developments. Changes in interest rates and changes in the financial str ength of issuers of lower-rated bonds may also affect underlying fund performance. The Fund is also subject to the risk that the investment adviser's decisions regarding asset classes and portfolio funds will not anticipate market trends successfully, resulting in a failure to preserve capital or lower total return. In addition, the Fund may buy and sell shares of the portfolio funds frequently. This may result in higher transaction costs and additional tax liability. This is not an offer of the shares of any other mutual fund mentioned herein.

18

Columbia Thermostat Fund (CTFAX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance may reflect any voluntary waivers or reimbursements of Fund expenses by the Adviser or any of its affiliates. Absent these waivers or reimbursement arrangements, performance results may be lower. Visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through December 31, 2007

Inception 3/3/03		1 year		3 years		Life of fund
Returns before taxes	NAV POP		8.19% 1.97		7.98% 5.87		11.43% 10.07
Returns after taxes on distributions	NAV POP		5.20 -0.85		5.49 3.43		9.60 8.26
Returns after taxes on distributions and sale of fund shares	NAV POP		6.01 1.92		5.79 3.99		9.13 7.94
S&P 500 (pretax)			5.49		8.62		14.27
Lehman Brothers U.S. Credit Intermediate Bond Index (pretax)			5.60		3.83		4.20
Lipper Flexible Portfolio Funds Index (pretax)			9.57		9.53		13.17

All results shown assume reinvestment of distributions.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.< /p>

Public offering price (POP) returns include the maximum sales charge of 5.75% for Class A shares. Net asset value (NAV) returns do not include sales charges or contingent deferred sales charges (CDSC).

The Fund's annual operating expense ratio, as stated in the current prospectus, reflects a contractual expense waiver or reimbursement that expires April 30, 2008. Class A shares expense ratios without and with the contractual waiver, including fees and expenses associated with the Fund's investment in other investment companies, are 1.35% and 1.19%, respectively. Absent the waiver or reimbursement, performance results would have been lower.

Columbia Thermostat Fund Asset Allocation

as a % of net assets as of 12/31/07

Columbia Thermostat Fund Portfolio Weightings

as a % of assets in each investment category as of 12/31/07

Stock Mutual Funds

Columbia Large Cap Enhanced Core Fund	25	%
Columbia Dividend Income Fund	20	%
Columbia Acorn Fund	15	%
Columbia Acorn International	15	%
Columbia Marsico Growth Fund	15	%
Columbia Acorn Select	10	%

Bond Mutual Funds

Columbia Intermediate Bond Fund	50	%
Columbia U.S. Treasury Index Fund	30	%
Columbia Conservative High Yield Fund	20	%

The Growth of a $10,000 Investment in Columbia Thermostat Fund (Class A)

March 3, 2003 through December 31, 2007

Illustration is based on a hypothetical $10,000 investment from inception in Class A shares of the Fund, which includes a 5.75% maximum initial sales charge. The indexes are unmanaged and returns for both the indexes and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $183.5 million

19

Columbia Acorn Fund

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	09/30/07		12/31/07
Additions
Information
AMIS Holdings		3,355,000		3,782,000
Blackbaud		1,326,000		1,800,000
Ciena		370,000		540,000
Cogent Communications		2,000,000		2,836,000
Dolby Laboratories		924,000		1,150,000
Epicor		2,500,000		3,500,000
FARO Technologies		860,000		1,044,000
General Communications		0		2,241,000
II-VI		2,257,000		2,400,000
Informatica		4,000,000		4,095,000
IPG Photonics		1,237,000		1,800,000
Jupiter Telecommunications (Japan)		70,000		88,000
Kenexa		1,868,000		2,425,000
Mediacom Communications		1,250,000		1,500,000
MetroPCS Communications		175,000		1,000,000
Netgear		932,000		1,110,000
Polycom		1,665,000		1,840,000
Quality Systems		0		1,510,000
Red Hat		1,600,000		3,000,000
Sanmina-SCI		26,000,000		29,500,000
Scientific Games		2,850,000		3,000,000
SRA International		1,050,000		1,150,000
Stratasys		650,000		775,000
Supertex		820,000		900,000
Switch & Data Facilities		900,000		2,000,000
Teradata		0		1,290,000
THQ		2,000,000		2,200,000
Time Warner Telecom		6,500,000		8,000,000
VeriFone Holdings		0		450,000
Viad		461,000		1,453,000
VisionChina Media (China)		0		1,250,000
Industrial Goods & Services
Acuity Brands		0		701,000
Administaff		1,900,000		2,025,000
Albany International		1,050,000		1,260,000
Allied Waste Industries		0		2,200,000
Aptargroup		146,000		300,000
Cytec Industries		400,000		500,000
Greif		400,000		600,000
Interline Brands		1,200,000		1,700,000
Kaydon		1,300,000		1,696,000
Martin Marietta Materials		650,000		750,000
MOOG		196,000		573,000
Oshkosh Truck		0		900,000
Texas Industries		0		450,000
Toro		833,000		1,100,000
TrueBlue		0		2,300,000

	Number of Shares
	09/30/07		12/31/07
Industrial Goods & Services—continued
Vulcan Materials		325,000		775,000
Wavin (Netherlands)		611,460		622,187
Zumtobel (Austria)		500,000		750,000
Consumer Goods & Services
American Woodmark		0		600,000
Choice Hotels		425,000		1,300,000
Church & Dwight		126,000		161,000
Fleetwood Enterprises		765,000		1,765,000
Pinnacle Entertainment		3,850,000		4,050,000
Smart Balance		0		1,500,000
Thor Industries		785,000		1,050,000
Winnebago		390,000		640,000
Finance
Aaron Rents		0		250,000
Bovespa (Brazil)		0		1,181,800
CAI International		1,200,000		1,500,000
Cohen & Steers		100,000		400,000
Conseco		5,950,000		6,500,000
Delphi Financial Group		1,000,000		1,600,000
GATX		520,000		771,000
H & E Equipment Services		300,000		600,000
KBW		350,000		550,000
MB Financial		920,000		1,240,000
Stewart Information Services		0		500,000
TriCo Bancshares		650,000		900,000
Valley National Bancorp		0		643,000
Energy & Minerals
Carrizo Oil & Gas		1,300,000		1,656,000
Dresser-Rand Group		1,448,000		1,675,000
Pacific Stratus Energy (Canada)		0		1,300,000
Petro Rubiales Energy - Warrants (Canada)		0		15,000,000
SBM Offshore (Netherlands)		550,000		640,200
ShawCor (Canada)		1,183,100		1,283,100
Tesco		1,640,000		1,804,000
Health Care
Alexion Pharmaceuticals		0		655,000
Arena Pharmaceuticals		2,020,000		2,500,000
Array Biopharma		2,160,000		2,660,000
Cephalon		1,050,000		1,115,000
Charles River Laboratories		1,085,000		1,245,000
Haemonetics		578,000		700,000
Henry Schein		929,000		1,090,000
Hologic		0		1,648,000
Illumina		225,000		725,000
Kinetic Concepts		0		435,000

See accompanying notes to financial statements.

20

	Number of Shares
	09/30/07		12/31/07
Additions (continued)
Health Care—continued
Medarex		2,000,000		2,550,000
MGI Pharma		1,010,000		1,090,000
Neurogen		2,190,000		2,300,000
Orthofix International		943,000		1,330,000
Pharmacopeia		825,000		1,675,000
QIAGEN (Netherlands)		1,250,000		1,775,000
Other Industries
BioMed Realty Trust		0		1,000,000
Federal Realty Investment Trust		575,000		860,000
Heartland Express		2,264,000		3,000,000
JB Hunt Transport Services		2,000,000		3,000,000
Jiangsu Expressway (China)		20,000,000		38,000,000
Rush Enterprises		0		956,000
Sales
Information
Actuate		5,306,000		5,000,000
Ceridian		3,000,000		0
CTS		1,310,000		631,000
Diebold		225,000		0
Dobson Communications		4,000,000		0
Hong Kong Exchanges and Clearing (Hong Kong)		6,500,000		3,300,000
Liberty Global, Series A		1,500,000		0
Liberty Global, Series C		2,050,000		1,500,000
Rogers		503,000		395,000
Singapore Exchange (Singapore)		5,000,000		4,000,000
Wincor Nixdorf (Germany)		570,000		460,000
Windstream		1,000,000		0
Industrial Goods & Services
Carbone Lorraine (France)		400,000		334,000
Florida Rock		1,900,000		0
Geberit (Switzerland)		170,000		0
Genlyte Group		2,600,000		950,000
Kingspan Group (Ireland)		444,400		413,100
Labor Ready		2,300,000		0
Neopost (France)		112,000		0
Spartech		1,050,000		0
USG People (Netherlands)		750,000		435,000
UTI Worldwide		2,700,000		2,500,000
Worthington Industries		320,000		0
Consumer Goods & Services
Carter's		918,000		0
Chico's FAS		9,130,000		7,600,000
Christopher & Banks		3,743,000		2,800,000
Hansen Natural		1,800,000		1,600,000
Natura Cosmeticos		1,100,000		0

	Number of Shares
	09/30/07		12/31/07
Consumer Goods & Services—continued
Nobia (Sweden)		2,960,000		0
Station Casinos		400,000		0
Finance
Eaton Vance		5,250,000		4,805,000
Great Southern Bancorp		636,000		614,000
Greene County Bancshares		150,000		135,000
Housing Development Finance (India)		1,700,000		1,350,000
Nuveen Investments		1,303,000		0
TCF Financial		2,156,000		1,800,000
United America Indemnity		1,550,000		0
Energy & Minerals
Aracruz Celulose		550,000		0
CARBO Ceramics		750,000		706,000
Key Energy Services		170,000		0
Rowan		1,161,000		600,000
St. Mary Land & Exploration		300,000		100,000
Talisman Energy (Canada)		4,900,000		4,000,000
Tullow Oil (United Kingdom)		9,315,000		4,629,000
Health Care
Arrow International		905,000		0
Coventry Health Care		500,000		0
Cytyc		2,102,000		0
Dade Behring		550,000		0
Endo Pharmaceuticals		1,300,000		0
La Jolla Pharmaceutical		359,000		97,000
LCA-Vision		1,125,000		0
Lexicon Genetics		3,100,000		2,035,000
Myriad Genetics		650,000		550,000
Nobel Biocare Holding (Switzerland)		75,000		0
Polymedica		1,025,000		0
Rhoen-Klinikum (Germany)		2,000,000		1,650,000
Synthes (Switzerland)		315,000		0
Other Industries
Brandywine Realty		1,020,000		0
China Shipping Development (China)		14,120,000		7,820,000

See accompanying notes to financial statements.

21

Columbia Acorn Fund

Statement of Investments, December 31, 2007

Number of Shares			Value (000)
				Equities: 95.9%
Information 26.2%
		> Business Software 3.9%
	1,400,000	Micros Systems (a)	$	98,224
		Information Systems for Restaurants & Hotels
	12,400,000	Novell (a)		85,188
		Directory, Operating System & Identity Management Software
	4,095,000	Informatica (a)		73,792
		Enterprise Data Integration Software
	3,000,000	Red Hat (a)		62,520
		Maintenance & Support for Opensource
	1,800,000	Avid Technology (a)		51,012
		Digital Nonlinear Editing Software & Systems
	1,400,000	Concur Technologies (a)		50,694
		Web Enabled Cost & Expense Management Software
	1,800,000	Blackbaud		50,472
		Software & Services for Non-profits
	2,425,000	Kenexa (a)(b)		47,094
		Recruiting & Workforce Management Solutions
	1,510,000	Quality Systems (b)		46,040
		IT Systems for Medical Groups & Ambulatory Care Centers
	2,500,000	Radiant Systems (a)(b)		43,075
		Point of Sale Systems: Convenient Stores & Restaurants
	1,007,000	ANSYS (a)		41,750
		Simulation Software for Engineers & Designers
	3,500,000	Epicor (a)(b)		41,230
		Software Systems to Run Small Businesses
	5,000,000	Actuate (a)(b)		38,850
		Information Delivery Software & Solutions
	1,800,000	Parametric Technology (a)		32,130
		Engineering Software & Services
	1,000,000	Cadence Design Systems (a)		17,010
		Electronic Design Automation Software
				779,081
		> Computer Hardware & Related Equipment 3.6%
	3,800,000	Amphenol		176,206
		Electronic Connectors
	2,280,000	Belden CDT (b)		101,460
		Specialty Cable
	2,400,000	II-VI (a)(b)		73,320
		Laser Components
	1,150,000	Dolby Laboratories (a)		57,178
		Audio Technology for Consumer Electronics
	1,426,000	Nice Systems (Israel) (a)		48,940
		Audio & Video Recording Solutions
	460,000	Wincor Nixdorf (Germany)		43,350
		Retail POS Systems & ATM Machines
	1,110,000	Netgear (a)		39,594
		Networking Products for Small Business & Home
	1,290,000	Teradata (a)		35,359
		Enterprise Data Warehouse Systems
	945,000	Zebra Technologies (a)		32,791
		Bar Code Printers

Number of Shares			Value (000)
	1,027,000	Avocent (a)	$	23,939
		Computer Control Switches
	775,000	Stratasys (a)		20,026
		Rapid Prototyping Systems
	735,000	Excel Technology (a)(b)		19,918
		Laser Systems & Electro-optical Components
	395,000	Rogers (a)		17,131
		PCB Laminates & High-performance Foams
	450,000	VeriFone Holdings (a)		10,463
		Point of Sale Systems
	500,000	Intermec (a)		10,155
		Bar Code & Wireless LAN Systems
	631,000	CTS		6,266
		Electronic Components, Sensors & Electronics Manufacturing Solutions
				716,096
		> Instrumentation 2.6%
	5,600,000	Flir Systems (a)		175,280
		Infrared Cameras
	3,070,000	Trimble Navigation (a)		92,837
		GPS-based Instruments
	750,000	Mettler Toledo (a)		85,350
		Laboratory Equipment
	800,000	Varian (a)		52,240
		Analytical Instruments
	600,000	Dionex (a)		49,716
		Ion & Liquid Chromatography
	1,800,000	IPG Photonics (a)		35,982
		Fiber Lasers
	1,044,000	FARO Technologies (a)(b)		28,376
		Precision Measurement Equipment
				519,781
		> Gaming Equipment & Services 2.0%
	3,150,000	Bally Technologies (a)(b)		156,618
		Slot Machines & Software
	2,750,000	International Game Technology		120,807
		Slot Machines & Progressive Slots
	3,000,000	Scientific Games (a)		99,750
		Lottery Services Provider
	2,430,000	Shuffle Master (a)(b)		29,136
		Card Shufflers & Casino Games
				406,311
		> Mobile Communications 2.0%
	4,500,000	Crown Castle International (a)		187,200
		Communications Towers
	3,500,000	American Tower (a)		149,100
		Communications Towers in USA & Mexico
	600,000	Telephone & Data Systems		37,560
		Cellular & Wireline Telephone Services
	1,000,000	MetroPCS Communications (a)		19,450
		Discount Cellular Telephone Services
	600,000	Globalstar (a)		4,800
		Satellite Mobile Voice & Data Carrier
				398,110
		> Internet Related 1.6%
	9,500,000	SkillSoft (a)(b)		90,820
		Web-based Learning Solutions (E-Learning)

See accompanying notes to financial statements.

22

Number of Shares			Value (000)
		> Internet Related—continued
	3,000,000	ValueClick (a)	$	65,700
		Internet Advertising
	700,000	Sohu.com (China) (a)		38,164
		Advertising on Chinese Internet Portal
	4,000,000	CNET Networks (a)		36,560
		Internet Advertising on Niche Websites
	2,000,000	Switch & Data Facilities (a)(b)		32,040
		Network Neutral Data Centers
	225,000	Equinix (a)		22,741
		Network Neutral Data Centers
	1,400,000	TheStreet.com		22,288
		Financial Information Website Publisher
	1,700,000	Marchex (b)		18,462
		Internet Advertising
				326,775
		> Semiconductors & Related Equipment 1.4%
	4,800,000	Integrated Device Technology (a)		54,288
		Communications Semiconductors
	2,250,000	Microsemi (a)		49,815
		Analog/Mixed-signal Semiconductors
	1,420,000	Littelfuse (a)(b)		46,803
		Little Fuses
	3,782,000	AMIS Holdings (a)		37,896
		Mixed-signal Semiconductors
	900,000	Supertex (a)(b)		28,161
		Mixed-signal Semiconductors
	3,000,000	Entegris (a)		25,890
		Semiconductor Wafer Shipping & Handling Products
	6,591,493	Everlight Electronics (Taiwan)		23,983
		Led Packager
	1,905,000	IXYS (a)(b)		15,278
		Power Semiconductors
				282,114
		> CATV 1.3%
	4,500,000	Discovery Holding (a)		113,130
		CATV Programming
	88,000	Jupiter Telecommunications (Japan) (a)		74,443
		Largest Cable Service Provider in Japan
	1,500,000	Liberty Global, Series C (a)		54,885
		Cable TV Franchises outside the USA
	130,000	Liberty Media Corp - Capital (a)		15,144
		CATV Holding Company
	1,500,000	Mediacom Communications (a)		6,885
		Cable Television Franchises
				264,487
		> Financial Processors 1.3%
	2,774,000	Global Payments		129,046
		Credit Card Processor
	3,300,000	Hong Kong Exchanges and Clearing (Hong Kong)		92,641
		Hong Kong Equity & Derivatives Market Operator
	4,000,000	Singapore Exchange (Singapore)		36,564
		Singapore Equity & Derivatives Market Operator
				258,251

Number of Shares			Value (000)
		> Telephone Services 1.2%
	8,000,000	Time Warner Telecom (a)(b)	$	162,320
		Fiber Optic Telephone/Data Services
	2,836,000	Cogent Communications (a)(b)		67,241
		Internet Data Pipelines
	2,241,000	General Communications (a)		19,609
		CATV, Web, Phone & Commercial Communications Provider in Alaska
				249,170
		> Telecommunications Equipment 0.9%
	15,600,000	Tellabs (a)		102,024
		Telecommunications Equipment
	1,840,000	Polycom (a)		51,115
		Video Conferencing Equipment
	540,000	Ciena (a)		18,420
		Optical Transport & Broadband Access Equipment
				171,559
		> Business Information & Marketing Services 0.7%
	1,453,000	Viad (b)		45,886
		Trade Show Services, Travel & Tours
	2,500,000	Navigant Consulting (a)(b)		34,175
		Financial Consulting Firm
	420,000	FTI Consulting (a)		25,889
		Financial Consulting Firm
	2,000,000	Voyager Learning (a)(b)		14,300
		Education Services for the K-12 Market
	2,500,000	Taylor Nelson Sofres (United Kingdom)		10,244
		Market Research
	250,000	Getty Images (a)		7,250
		Photographs for Publications & Electronic Media
	800,000	infoUSA		7,144
		Business Data for Sales Leads
				144,888
		> Publishing 0.6%
	1,200,000	NAVTEQ (a)		90,720
		Map Data for Electronic Devices
	800,000	Prisa (Spain)		14,875
		Leading Spanish-speaking Publisher
	1,300,000	Informa Group (United Kingdom)		11,891
		Global Publisher & Event Organizer
				117,486
		> Electronics Distribution 0.6%
	2,840,000	Avnet (a)		99,315
		Electronic Components Distribution
	710,000	Agilysys		10,735
		IT Distributor
				110,050
		> Contract Manufacturing 0.5%
	29,500,000	Sanmina-SCI (a)(b)		53,690
		Electronic Manufacturing Services
	1,475,000	Plexus (a)		38,734
		Electronic Manufacturing Services
	690,000	Jabil Circuit		10,536
		Electronic Manufacturing Services
				102,960

See accompanying notes to financial statements.

23

Columbia Acorn Fund

Statement of Investments, continued

Number of Shares			Value (000)
		> Computer Services 0.5%
	5,000,000	iGate (a)(b)	$	42,350
		IT & Business Process Outsourcing Services
	1,150,000	SRA International (a)		33,867
		Government IT Services
	4,600,000	AnswerThink (a)(b)		22,264
		IT Integration & Best Practice Research
				98,481
		> Consumer Software 0.4%
	2,200,000	THQ (a)		62,018
		Entertainment Software
	750,000	Activision (a)		22,275
		Entertainment Software
				84,293
		> Satellite Broadcasting & Services 0.4%
	2,755,000	SES Global (France)		72,241
		Satellite Broadcasting Services
				72,241
		> Television Programming 0.2%
	4,000,000	Lions Gate Entertainment (a)		37,680
		Film & TV Studio
				37,680
		> Radio 0.2%
	1,500,000	Cumulus Media (a)		12,060
		Radio Stations in Small Cities
	1,541,000	Salem Communications (b)		10,155
		Radio Stations for Religious Programming
	1,400,000	Saga Communications (a)(b)		8,246
		Radio Stations in Small- & Mid-sized Cities
	2,400,000	Spanish Broadcasting System (a)(b)		4,440
		Spanish Language Radio Stations
				34,901
		> TV Broadcasting 0.2%
	2,500,000	Entravision Communications (a)		19,575
		Spanish Language TV, Radio & Outdoor
	1,750,000	Gray Television		14,035
		Mid Market Affiliated TV Stations
				33,610
		> Advertising 0.1%
	1,250,000	VisionChina Media (China) (a)		10,625
		Advertising on Digital Screens in China's Mass Transit System
				10,625
Information: Total				5,218,950
Industrial Goods & Services 17.8%
		> Machinery 6.5%
	5,000,000	Ametek		234,200
		Aerospace/Industrial Instruments
	4,200,000	Donaldson (b)		194,796
		Industrial Air Filtration
	3,500,000	Clarcor (b)		132,895
		Mobile & Industrial Filters
	2,850,000	Pentair		99,209
		Pumps & Water Treatment

Number of Shares			Value (000)
	1,814,000	Mine Safety Appliances (b)	$	94,092
		Safety Equipment
	1,696,000	Kaydon (b)		92,500
		Specialized Friction & Motion Control Products
	2,250,000	Pall		90,720
		Filtration & Fluids Clarification
	2,200,000	ESCO Technologies (a)(b)		87,868
		Automatic Electric Meter Readers
	1,250,000	Nordson		72,450
		Dispensing Systems for Adhesives & Coatings
	2,700,000	Goodman Global (a)		66,258
		HVAC Equipment Manufacturer
	1,100,000	Toro		59,884
		Turf Maintenance Equipment
	900,000	Oshkosh Truck		42,534
		Specialty Truck Manufacturer
	573,000	MOOG (a)		26,249
		Motion Control Products for Aerospace, Defense & Industrial Markets
	360,000	Union Tool (Japan)		11,907
		Precision Drill Bit Manufacturer
				1,305,562
		> Other Industrial Services 2.9%
	5,500,000	Expeditors International of Washington		245,740
		International Freight Forwarder
	1,900,000	Forward Air (b)		59,223
		Freight Transportation Between Airports
	2,500,000	UTI Worldwide		49,000
		Global Logistics & Freight Forwarding
	2,300,000	TrueBlue (a)(b)		33,304
		Temporary Manual Labor
	2,000,000	American Reprographics (a)		32,960
		Document Management & Logistics
	2,000,000	American Commercial Lines (a)		32,480
		Operator/Builder of Inland Barges
	1,750,000	Mobile Mini (a)(b)		32,445
		Portable Storage Units Leasing
	1,122,000	Imtech (Netherlands)		27,576
		Engineering & Technical Services
	600,000	G&K Services		22,512
		Uniform Rental
	1,100,000	Intertek Testing (United Kingdom)		21,566
		Testing, Inspection, Certification Services
	615,000	TAL International Group		14,004
		Intermodal Freight Containers Leasing
				570,810
		> Industrial Materials & Specialty Chemicals 1.8%
	530,000	Novozymes (Denmark)		59,818
		Industrial Enzymes
	1,260,000	Albany International		46,746
		Paper Machine Clothing & Advanced Textiles
	23,000	Sika (Switzerland)		43,234
		Chemicals for Construction & Industrial Applications
	600,000	Greif		39,222
		Industrial Packaging
	1,378,000	Drew Industries (a)(b)		37,757
		RV & Manufactured Home Components

See accompanying notes to financial statements.

24

Number of Shares			Value (000)
		> Industrial Materials & Specialty Chemicals—continued
	195,000	Sociedad Quimica y Minera de Chile (Chile)	$	34,466
		Producer of Specialty Fertilizers, Lithium & Iodine
	500,000	Cytec Industries		30,790
		Aerospace Composites & Specialty Chemical
	334,000	Carbone Lorraine (France)		23,015
		Advanced Industrial Materials
	2,850,000	Kansai Paint (Japan)		20,673
		Paint Producer in Japan, India, China & Southeast Asia
	441,384	Koninklijke TenCate (Netherlands)		13,644
		Advanced Textiles & Industrial Fabrics
	300,000	Aptargroup		12,273
		Dispensing Systems for Consumer Products & Pharmaceuticals
	622,187	Wavin (Netherlands)		8,230
		Largest European Plastic Pipe Systems Company
				369,868
		> Industrial Distribution 1.7%
	1,300,000	WW Grainger		113,776
		Industrial Distribution
	1,925,000	Airgas		100,312
		Industrial Gas Distributor
	2,375,000	Watsco (b)		87,305
		HVAC Distribution
	1,700,000	Interline Brands (a)(b)		37,247
		Industrial Distribution
				338,640
		> Construction 1.3%
	750,000	Martin Marietta Materials		99,450
		Aggregates
	775,000	Vulcan Materials		61,294
		Aggregates, Concrete & Asphalt
	2,200,000	Simpson Manufacturing		58,498
		Wall Joint Maker
	450,000	Texas Industries		31,545
		Aggregates, Cement & Concrete
	413,100	Kingspan Group (Ireland)		6,226
		Building Insulation & Environmental Containers
				257,013
		> Electrical Components 1.0%
	950,000	Genlyte Group (a)		90,440
		Commercial Lighting Fixtures
	701,000	Acuity Brands		31,545
		Commercial Lighting Fixtures
	750,000	Zumtobel (Austria)		26,921
		Lighting Systems
	1,125,000	Ushio (Japan)		24,692
		Industrial Light Sources
	700,000	Legrand (France)		23,776
		Electrical Components
				197,374
		> Conglomerates 1.0%
	4,845,000	Hexagon (Sweden)		99,911
		Measurement Equipment & Polymers

Number of Shares			Value (000)
	2,758,309	Aalberts Industries (Netherlands)	$	54,367
		Flow Control & Heat Treatment
	600,000	Ibiden (Japan)		41,443
		Electronic Parts & Ceramics
				195,721
		> Outsourcing Services 0.7%
	2,300,000	Quanta Services (a)		60,352
		Electrical & Telecom Construction Services
	2,025,000	Administaff (b)		57,267
		Professional Employer Organization
	435,000	USG People (Netherlands)		11,661
		Temporary Staffing Services
	600,000	GP Strategies (a)		6,390
		Training Programs
				135,670
		> Waste Management 0.5%
	2,550,000	Waste Connections (a)		78,795
		Solid Waste Management
	2,200,000	Allied Waste Industries (a)		24,244
		Solid Waste Management
				103,039
		> Steel 0.4%
	2,860,000	Gibraltar Industries (b)		44,101
		Steel Processing & Building Products
	135,000	Vallourec (France)		36,343
		Oil, Gas & Industrial Seamless Tubes
				80,444
Industrial Goods & Services: Total				3,554,141
Consumer Goods & Services 15.1%
		> Retail 3.5%
	3,140,000	Abercrombie & Fitch		251,106
		Teen Apparel Retailer
	4,850,000	Urban Outfitters (a)		132,211
		Apparel & Home Specialty Retailer
	1,975,000	J Crew Group (a)		95,214
		Multi-channel Branded Retailer
	7,600,000	Chico's FAS (a)		68,628
		Women's Specialty Retailer
	1,200,000	Gaiam (a)(b)		35,616
		Healthy Living Catalogs & E-Commerce
	2,800,000	Christopher & Banks (b)		32,060
		Women's Apparel Retailer
	1,223,000	AnnTaylor Stores (a)		31,260
		Women's Apparel Retailer
	775,000	Genesco (a)		29,295
		Multi-concept Branded Footwear Retailer
	1,564,000	RONA (Canada) (a)		27,019
		Leading Canadian Do-it-yourself Retailer
	30,000	Lululemon Athletica (a)		1,421
		Premium Active Apparel Retailer
				703,830
		> Other Consumer Services 1.7%
	2,000,000	ITT Educational Services (a)(b)		170,540
		Post-secondary Degree Services

See accompanying notes to financial statements.

25

Columbia Acorn Fund

Statement of Investments, continued

Number of Shares			Value (000)
		> Other Consumer Services—continued
	1,275,000	Weight Watchers International	$	57,604
		Weight Loss Programs
	1,120,000	NutriSystem (a)		30,218
		Weight Loss Programs
	1,500,000	Universal Technical Institute (a)(b)		25,500
		Vocational Training
	2,550,000	Princeton Review (a)(b)		21,242
		College Preparation Courses
	2,100,000	Park24 (Japan)		16,172
		Parking Lot Operator
	110,000	Pierre & Vacances (France)		15,197
		Vacation Apartment Lets
	100,000	Lincoln Technical Institute (a)		1,472
		Vocational Training
				337,945
		> Apparel 1.6%
	7,330,000	Coach (a)		224,152
		Designer & Retailer of Branded Leather Accessories
	3,000,000	Billabong International (Australia)		38,982
		Action Sports Apparel Brand Manager
	1,069,000	Oxford Industries (b)		27,548
		Branded & Private Label Apparel
	900,000	True Religion Apparel (a)		19,215
		Premium Denim
				309,897
		> Travel 1.6%
	2,390,000	Vail Resorts (a)(b)		128,606
		Ski Resort Operator & Developer
	4,000,000	Expedia (a)		126,480
		Online Travel Services Company
	1,300,000	Choice Hotels		43,160
		Franchisor of Budget Hotel Brands
	601,000	Ambassadors Group		11,004
		Educational Student Travel Services
				309,250
		> Nondurables 1.4%
	2,860,000	Scotts Miracle-Gro		107,021
		Consumer Lawn & Garden Products
	1,010,000	Chattem (a)(b)		76,296
		Personal Care Products
	2,500,000	Jarden (a)		59,025
		Branded Household Products
	1,900,000	Helen of Troy (a)(b)		32,566
		Hair Dryers & Curling Irons
	161,000	Church & Dwight		8,705
		Branded Household & Personal Care Products
				283,613
		> Furniture & Textiles 1.3%
	4,000,000	Herman Miller (b)		129,560
		Office Furniture
	2,000,000	HNI		70,120
		Office Furniture & Fireplaces
	3,400,000	Knoll (b)		55,862
		Office Furniture
	600,000	American Woodmark		10,908
		Kitchen Cabinet Manufacturer
				266,450

Number of Shares			Value (000)
		> Casinos & Gaming 1.2%
	1,700,000	Penn National Gaming (a)	$	101,235
		Regional Casino Operator
	4,050,000	Pinnacle Entertainment (a)(b)		95,418
		Regional Casino Operator
	2,380,000	Intralot (Greece)		46,898
		Lottery & Gaming Systems & Services
	226,000	Lakes Entertainment (a)		1,566
		Native American Casinos Development
				245,117
		> Leisure Products 1.0%
	1,416,000	Speedway Motorsports		44,009
		Motorsports Racetrack Owner & Operator
	1,025,000	International Speedway		42,209
		Largest Motorsports Racetrack Owner & Operator
	1,050,000	Thor Industries		39,911
		RV & Bus Manufacturer
	800,000	Harley-Davidson		37,368
		Motorcycles & Related Merchandise
	640,000	Winnebago		13,453
		Premier Motorhome Maker
	5,410,390	Ducati Motor (Italy) (a)		11,056
		Motorcycles & Related Merchandise
	1,765,000	Fleetwood Enterprises (a)		10,555
		RV & Manufactured Home Maker
				198,561
		> Restaurants 0.6%
	2,145,000	Sonic (a)		46,975
		Quick Service Restaurant
	1,000,000	Red Robin Gourmet Burgers (a)(b)		31,990
		Casual Dining Restaurant
	1,150,000	Cheesecake Factory (a)		27,267
		Casual Dining Restaurants
	1,800,000	AFC Enterprises (a)(b)		20,376
		Popeyes Restaurants
				126,608
		> Food & Beverage 0.6%
	1,600,000	Hansen Natural (a)		70,864
		Alternative Beverages
	1,000,000	IAWS Group (Ireland)		22,135
		Baked Goods
	1,500,000	Smart Balance (a)		16,395
		Healthy Food Products
				109,394
		> Consumer Goods Distribution 0.3%
	2,890,000	Pool (b)		57,309
		Distributor of Swimming Pool Supplies & Equipment
				57,309
		> Cruise Lines 0.1%
	400,000	Carnival		17,796
		Largest Cruise Line
				17,796

See accompanying notes to financial statements.

26

Number of Shares			Value (000)
		> Other Entertainment 0.1%
	435,000	CTS Eventim (Germany)	$	16,719
		Event Ticket Sales
				16,719
		> Other Durable Goods 0.1%
	900,000	Champion Enterprises (a)		8,478
		Manufactured Homes
	172,000	Cavco Industries (a)		5,821
		Higher End Manufactured Homes
				14,299
Consumer Goods & Services: Total				2,996,788
Finance 13.0%
		> Insurance 4.2%
	3,965,000	HCC Insurance Holdings		113,716
		Specialty Insurance
	2,390,000	Philadelphia Consolidated Holding (a)		94,047
		Specialty Insurance
	1,748,000	Leucadia National		82,331
		Insurance Holding Company
	6,500,000	Conseco (a)		81,640
		Life, Long-term Care & Medical Supplement Insurance
	1,200,000	Assurant		80,280
		Specialty Insurance
	149,000	Markel (a)		73,174
		Specialty Insurance
	1,600,000	Delphi Financial Group		56,448
		Group Employee Benefit Products & Services
	1,000,000	Endurance Specialty Holdings		41,730
		Commercial Lines Insurance/Reinsurance
	995,000	Protective Life		40,815
		Life Insurance
	740,000	Stancorp Financial Group		37,281
		Group Life & Disability Insurance
	1,420,000	Selective Insurance Group		32,646
		Commercial & Personal Lines Insurance
	1,000,000	Aspen Insurance		28,840
		Commercial Lines Insurance/Reinsurance
	600,000	National Financial Partners		27,366
		Distributor of Life Insurance, Group Benefits & Investment Advisory Services
	2,000,000	Meadowbrook Insurance Group (a)(b)		18,820
		Specialty Insurance Products & Services
	280,000	April Group (France)		18,796
		Insurance Policy Construction
	500,000	Stewart Information Services		13,045
		Title Company
				840,975
		> Banks 3.0%
	3,500,000	BOK Financial (b)		180,950
		Tulsa Based S.W. Bank
	3,511,000	Associated Banc-Corp		95,113
		Midwest Bank
	4,246,000	Glacier Bancorp (b)		79,570
		Mountain States Bank
	1,222,000	Chittenden		43,528
		New England Bank

Number of Shares			Value (000)
	1,240,000	MB Financial	$	38,229
		Chicago Bank
	1,800,000	TCF Financial		32,274
		Great Lakes Bank
	1,437,000	West Coast Bancorp (b)		26,584
		Portland Small Business Bank
	530,000	First Financial Bankshares		19,955
		West Texas Bank
	900,000	TriCo Bancshares (b)		17,370
		California Central Valley Community Bank
	1,312,000	West Bancorporation (b)		17,108
		Des Moines Commercial Bank
	614,000	Great Southern Bancorp		13,483
		Missouri Real Estate Lender
	643,000	Valley National Bancorp		12,256
		New Jersey/New York Bank
	400,000	First Mutual Bancshares (b)		10,572
		Seattle Community Bank
	450,000	First Busey		8,937
		Illinois Bank
	135,000	Greene County Bancshares		2,592
		Tennessee Bank
				598,521
		> Brokerage & Money Management 2.4%
	4,805,000	Eaton Vance		218,195
		Specialty Mutual Funds
	6,168,000	SEI Investments		198,425
		Mutual Fund Administration & Investment Management
	1,181,800	Bovespa (Brazil) (a)		22,773
		Brazil Equity & Derivative Exchange
	450,000	Investment Technology Group (a)		21,415
		Electronic Trading
	550,000	KBW (a)		14,075
		Investment Bank to Financial Industry
	400,000	Cohen & Steers		11,988
		Top REIT Fund Manager
				486,871
		> Savings & Loans 2.0%
	11,585,000	People's United		206,213
		Connecticut Savings & Loan
	1,350,000	Housing Development Finance (India)		96,864
		Indian Mortgage Lender
	2,725,000	Washington Federal		57,525
		Traditional Thrift
	774,000	Anchor Bancorp Wisconsin		18,204
		Wisconsin Thrift
	200,000	Downey Financial		6,222
		Option Arm Lender
	360,000	Provident New York Bancorp		4,651
		New York State Thrift
				389,679
		> Finance Companies 1.4%
	7,235,000	AmeriCredit (a)(b)		92,536
		Auto Lending
	1,675,000	World Acceptance (a)(b)		45,191
		Personal Loans
	1,700,000	McGrath Rentcorp (b)		43,775
		Temporary Space & IT Rentals

See accompanying notes to financial statements.

27

Columbia Acorn Fund

Statement of Investments, continued

Number of Shares			Value (000)
		> Finance Companies—continued
	771,000	GATX	$	28,280
		Rail Car Lessor
	1,500,000	CAI International (a)(b)		15,780
		International Container Leasing & Management
	1,100,000	Marlin Business Services (a)(b)		13,266
		Small Equipment Leasing
	850,000	Electro Rent		12,623
		Test & Measurement Rentals
	600,000	H & E Equipment Services (a)		11,328
		Heavy Equipment Leasing
	500,000	Rent-A-Center (a)		7,260
		Rent to Own
	250,000	Aaron Rents		4,810
		Rent to Own
				274,849
Finance: Total				2,590,895
Energy & Minerals 10.9%
		> Oil Services 5.2%
	5,640,000	FMC Technologies (a)		319,788
		Oil & Gas Wellhead Manufacturer
	3,900,000	Fugro (Netherlands) (b)		298,939
		Oilfield Services
	1,200,000	Atwood Oceanics (a)		120,288
		Offshore Drilling Contractor
	1,675,000	Dresser-Rand Group (a)		65,409
		Largest Manufacturer of Compressors
	1,804,000	Tesco (a)		51,721
		Developing New Well Drilling Technologies
	1,283,100	ShawCor (Canada)		45,944
		Oil & Gas Pipeline Products
	1,988,000	Tetra Technologies (a)		30,953
		U.S. Based Service Company with Life of Field Approach
	706,000	CARBO Ceramics		26,263
		Natural Gas Well Stimulants
	600,000	Rowan		23,676
		Offshore Drilling Contractor
	640,200	SBM Offshore (Netherlands)		20,081
		Builds & Leases Offshore Vessels to Process & Store Crude Oil
	195,000	Exterran Holdings (a)		15,951
		Natural Gas Compressor Rental & Fabrication
	1,580,000	Enerflex Systems (Canada)		14,264
		Natural Gas Compresser Rental & Fabrication
				1,033,277
		> Oil & Gas Producers 4.9%
	2,700,000	Ultra Petroleum (a)		193,050
		Oil & Gas Producer
	3,125,000	XTO Energy		160,500
		Oil & Gas Producer
	2,400,000	Equitable Resources		127,872
		Natural Gas Producer & Utility
	1,800,000	Southwestern Energy (a)		100,296
		Oil & Gas Producer
	1,656,000	Carrizo Oil & Gas (a)(b)		90,666
		Explores for Natural Gas & Crude Oil

Number of Shares			Value (000)
	1,500,000	Range Resources	$	77,040
		Oil & Gas Producer
	4,000,000	Talisman Energy (Canada)		74,533
		Oil & Gas Producer
	4,629,000	Tullow Oil (United Kingdom)		59,726
		Oil & Gas Producer
	1,400,000	Denbury Resources (a)		41,650
		Oil Producer Using Co2 Injection
	15,000,000	Petro Rubiales Energy (Canada) (a)		22,038
		Oil Production & Exploration in Colombia
	1,300,000	Pacific Stratus Energy (Canada) (a)		16,149
		Oil & Gas Exploration in Colombia
	2,750,000	Vaalco Energy (a)		12,787
		Oil & Gas Producer
	100,000	St. Mary Land & Exploration		3,861
		Oil & Gas Producer
				980,168
		> Mining 0.7%
	7,725,000	Uranium One (South Africa) (a)		69,114
		Uranium Mines in South Africa, Kazakhstan, Australia & the U.S.
	2,900,000	Jubilee Mines (Australia)		57,636
		Nickel Mining in Australia
	1,000,000	Ivanhoe Mines (Canada) (a)		10,943
		Copper Mine Project in Mongolia
				137,693
		> Oil Refining, Marketing & Distribution 0.1%
	435,000	Oneok		19,475
		Natural Gas Distribution, Pipeline Processing & Trading
				19,475
Energy & Minerals: Total				2,170,613
Health Care 8.4%
		> Biotechnology & Drug Delivery 2.3%
	4,000,000	BioMarin (a)		141,600
		Biotech Focused on Orphan Diseases
	655,000	Alexion Pharmaceuticals (a)		49,145
		Biotech Focused on Orphan Diseases
	2,550,000	PDL BioPharma (a)		44,676
		Proprietary Monoclonal Antibodies
	3,720,000	Seattle Genetics (a)(b)		42,408
		Antibody-based Therapies for Cancer
	865,000	Amylin (a)		32,005
		Biotech Company Focused on Diabetes & Obesity
	2,550,000	Medarex (a)		26,571
		Humanized Antibodies
	550,000	Myriad Genetics (a)		25,531
		Drugs/Diagnostics Hybrid
	2,660,000	Array Biopharma (a)(b)		22,397
		Drugs for Cancer & Inflammatory Diseases
	2,500,000	Arena Pharmaceuticals (a)		19,575
		Novel Drug Targeting Technology
	1,650,000	Nektar Therapeutics (a)		11,071
		Drug Delivery Technologies
	2,520,000	Decode Genetics (a)		9,274
		Drugs for Heart Attack, Asthma & Vascular Disease

See accompanying notes to financial statements.

28

Number of Shares			Value (000)
		> Biotechnology & Drug Delivery—continued
	1,675,000	Pharmacopeia (a)(b)	$	7,990
		Biotech Company with Broad Early-stage Pipeline
	2,300,000	Neurogen (a)(b)		7,935
		Development-stage Biotech Focused on Neurology
	2,035,000	Lexicon Genetics (a)		6,166
		Drug Discovery
	1,025,000	Nuvelo (a)		1,876
		Development-stage Biotech Focused on Cardiovascular/Cancer
	187,500	Locus Pharmaceuticals, Series A-1, Pfd. (a)(c)		488
	96,644	Locus Pharmaceuticals, Series B-1, Pfd. (a)(c)		251
		High Throughput Rational Drug Design
	1,249,999	Perlegen Sciences (a)(c)		400
		Large Scale Gene Sequencing
	97,000	La Jolla Pharmaceutical (a)		380
		Lupus Treatment
	359,944	MicroDose Technologies (a)(c)		288
		Drug Inhaler Development
				450,027
		> Medical Equipment & Devices 2.1%
	1,648,000	Hologic (a)		113,119
		Diagnostic & Medical Imaging Equipment for Women's Health
	1,330,000	Orthofix International (a)(b)		77,100
		Bone Fixation & Stimulation Devices
	1,000,000	Edwards Lifesciences (a)		45,990
		Heart Valves
	870,000	Vital Signs (b)		44,474
		Anesthesia, Respiratory & Sleep Products
	700,000	Haemonetics (a)		44,114
		Blood & Plasma Collection Equipment
	725,000	Illumina (a)		42,963
		Leading Tools & Service Provider for Genetic Analysis
	435,000	Kinetic Concepts (a)		23,299
		Wound Healing & Tissue Repair
	552,000	Advanced Medical Optics (a)		13,541
		Medical Devices for Eye Care
				404,600
		> Health Care Services 1.6%
	1,245,000	Charles River Laboratories (a)		81,921
		Pharmaceutical Research
	1,650,000	Rhoen-Klinikum (Germany)		51,605
		Health Care Services
	1,300,000	Lincare Holdings (a)		45,708
		Home Health Care Services
	2,250,000	PSS World Medical (a)		44,032
		Medical Supplies
	3,000,000	Eresearch Technology (a)(b)		35,460
		Clinical Research Services
	1,177,000	OPG Groep (Netherlands)		32,519
		Health Care Supplies & Pharmacies
	900,000	Omnicare		20,529
		Pharmacy Services for Nursing Homes

Number of Shares			Value (000)
	600,000	Healthcare Services Group	$	12,708
		Outsourced Services to Long-term Care Industry
				324,482
		> Medical Supplies 1.4%
	1,090,000	Henry Schein (a)		66,926
		Largest Distributor of Healthcare Products
	1,200,000	Owens & Minor		50,916
		Distribution of Medical Supplies
	1,250,000	ICU Medical (a)(b)		45,013
		Intravenous Therapy Products
	1,775,000	QIAGEN (Netherlands) (a)		37,364
		Life Science Company; DNA/RNA Purification
	486,000	Techne (a)		32,100
		Cytokines, Antibodies & other Reagents for Life Science
	700,000	Cooper		26,600
		Contact Lens Manufacturer
	790,000	Meridian Biosciences		23,763
		Niche Diagnostics/Life Science Company
				282,682
		> Pharmaceuticals 1.0%
	1,115,000	Cephalon (a)		80,012
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	1,090,000	MGI Pharma (a)		44,178
		Specialty Pharmaceuticals for Oncology & Acute Care
	1,000,000	Medicis Pharmaceutical		25,970
		Specialty Pharmaceuticals for Dermatology
	3,100,000	United Drug (Ireland)		17,876
		Irish Pharmaceutical Wholesaler & Outsourcer
	4,000,000	QLT (a)(b)		17,680
		Specialty Pharmaceuticals for Ophthalmology & Dermatology
	1,200,000	Collagenex Pharmaceuticals (a)(b)		11,460
		Specialty Pharmaceuticals for Dermatology
	1,780,000	Barrier Therapeutics (a)(b)		7,013
		Specialty Pharmaceuticals for Dermatology
				204,189
Health Care: Total				1,665,980
Other Industries 4.5%
		> Real Estate 2.9%
	2,180,000	Gaylord Entertainment (a)(b)		88,225
		Convention Hotels
	860,000	Federal Realty Investment Trust		70,649
		Shopping Centers
	4,500,000	DiamondRock Hospitality		67,410
		Hotel Owner
	1,398,000	Forest City Enterprises, Class B (b)		62,267
		Commercial & Residential Property Developer
	650,000	SL Green Realty		60,749
		Manhattan Office Buildings
	1,320,000	General Growth Properties		54,358
		Regional Shopping Malls
	635,000	Macerich Company		45,123
		Regional Shopping Malls
	850,000	Digital Realty Trust		32,615
		Technology-focused Office Buildings

See accompanying notes to financial statements.

29

Columbia Acorn Fund

Statement of Investments, continued

Number of Shares or Principal Amount (000)			Value (000)
		> Real Estate—continued
	1,720,000	Kite Realty Group (b)	$	26,264
		Community Shopping Centers
	900,000	American Campus Communities		24,165
		Student Housing
	628,000	Parkway Properties		23,223
		Office Buildings
	1,000,000	BioMed Realty Trust		23,170
		Life Science-focused Office Buildings
	8,200	Kenedix (Japan)		13,194
		Real Estate Investment Management
	37,407	Security Capital European Realty (Luxembourg) (a)(c)(d)		—
		Self Storage Properties
				591,412
		> Transportation 1.3%
	3,000,000	JB Hunt Transport Services		82,650
		Truck & Intermodal Carrier
	826,200	Grupo Aeroportuario del Surest (Mexico)		50,580
		Cancun & Cozumel Airport Operator
	3,000,000	Heartland Express		42,540
		Regional Trucker
	38,000,000	Jiangsu Expressway (China)		41,007
		Chinese Toll Road Operator
	7,820,000	China Shipping Development (China)		20,393
		China's Dominant Shipper for Oil & Coal
	956,000	Rush Enterprises (a)		17,380
		Truck Distribution
				254,550
		> Regulated Utilities 0.3%
	1,800,000	Northeast Utilities		56,358
		Regulated Electric Utility
				56,358
Other Industries: Total				902,320
Total Equities: 95.9% (Cost: $12,297,767)				19,099,687
Short-Term Obligations 4.2%
$	100,000	Hewlett Packard (e) 4.23% Due 1/07/08 – 1/08/08		99,924
	80,000	Nestle Capital (e) 4.15% Due 1/11/08 – 1/24/08		79,862
	50,000	Emerson Electric (e) 4.20% Due 1/02/08		49,994
		General Electric Capital:
	50,000	4.10% Due 1/03/08		49,989
	50,000	4.20% Due 1/17/08		49,907
		Hershey Foods: (e)
	50,000	4.48% Due 1/07/08		49,963
	20,000	4.23% Due 1/08/08		19,984

Principal Amount (000)			Value (000)
		Toyota Motor Credit:
$	50,000	4.18% Due 1/09/08	$	49,954
	25,000	4.15% Due 1/04/08		24,991
	25,000	4.20% Due 1/18/08		24,950
		United Parcel Service: (e)
	50,000	4.36% Due 1/10/08		49,945
	50,000	4.365% Due 1/11/08		49,939
	50,000	Caterpillar Finance 4.22% Due 1/14/08		49,924
	41,635	Genentech (e) 4.26% Due 1/18/08		41,551
	41,100	IBM International Group (e) 4.39% Due 1/11/08		41,050
		Toyota Motor Credit:
	19,925	IBM Corporation (e) 4.21% Due 1/02/08		19,923
	19,000	Nestle Finance 4.40% Due 1/11/08		18,977
	10,000	Walgreen Co. (e) 4.20% Due 1/02/08		9,999
	57,143	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by U.S. Government Agency Obligations with various maturities to 7/18/16, market value $58,287 (repurchase proceeds $57,153)		57,143
(Amortized Cost: $837,969)				837,969
Total Investments: 100.1% (Cost: $13,135,736)(f)(g)				19,937,656
Cash and Other Assets Less Liabilities: (0.1)%				(16,310	)
Total Net Assets: 100%			$	19,921,346

See accompanying notes to financial statements.

30

> Notes to Statement of Investments (dollar values in thousands)

(a)  Non-income producing security.

(b)  An affiliate may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in these affiliated companies during the twelve months ended December 31, 2007, are as follows:

Affiliates	Balance of Shares Held 12/31/06		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/07		Value		Dividend
Actuate		6,000,000		-		1,000,000		5,000,000	$	38,850	$	-
Administaff		1,670,000		355,000		-		2,025,000		57,267		839
AFC Enterprises		1,600,000		200,000		-		1,800,000		20,376		-
Agile Software*		3,500,000		-		3,500,000		-		-		-
AmeriCredit		6,500,000		735,000		-		7,235,000		92,536		-
Anchor Bancorp Wisconsin*		1,178,000		-		404,000		774,000		18,204		680
AnswerThink		4,600,000		-		-		4,600,000		22,264		-
Array Biopharma		1,780,000		880,000		-		2,660,000		22,397		-
Bally Technologies		3,500,000		-		350,000		3,150,000		156,618		-
Barrier Therapeutics		1,321,000		459,000		-		1,780,000		7,013		-
Belden CDT		1,945,000		335,000		-		2,280,000		101,460		430
BOK Financial		2,605,000		895,000		-		3,500,000		180,950		2,322
CAI International		-		1,500,000		-		1,500,000		15,780		-
Carrizo Oil & Gas		-		1,656,000		-		1,656,000		90,666		-
Chattem		1,010,000		-		-		1,010,000		76,296		-
Chico's FAS*		7,080,000		2,050,000		1,530,000		7,600,000		68,628		-
Christopher & Banks		3,743,000		-		943,000		2,800,000		32,060		842
Clarcor		3,500,000		-		-		3,500,000		132,895		1,041
Cogent Communications		1,000,000		1,836,000		-		2,836,000		67,241		-
Collagenex Pharmaceuticals		830,000		370,000		-		1,200,000		11,460		-
Concur Technologies*		2,131,000		-		731,000		1,400,000		50,694		-
Cytokinetics*		2,000,000		-		2,000,000		-		-		-
Dobson Communications*		8,000,000		-		8,000,000		-		-		-
Donaldson		3,600,000		600,000		-		4,200,000		194,796		1,506
Drew Industries		1,228,000		150,000		-		1,378,000		37,757		-
Enerflex Systems*		2,280,000		8,100		708,100		1,580,000		14,264		1,316
Epicor		-		3,500,000		-		3,500,000		41,230		-
Eresearch Technology		2,300,000		700,000		-		3,000,000		35,460		-
ESCO Technologies		2,200,000		-		-		2,200,000		87,868		-
Excel Technology		625,000		110,000		-		735,000		19,918		-
FARO Technologies		-		1,044,000		-		1,044,000		28,376		-
First Mutual Bancshares		400,000		-		-		400,000		10,572		144
Fleetwood Enterprises*		4,690,000		1,000,000		3,925,000		1,765,000		10,555		-
Forest City Enterprises, Class B		1,398,000		-		-		1,398,000		62,267		419
Forward Air		1,900,000		-		-		1,900,000		59,223		532
Fugro		2,928,301		971,699		-		3,900,000		298,939		3,860
Gaiam		1,200,000		-		-		1,200,000		35,616		-
Gaylord Entertainment		1,760,000		420,000		-		2,180,000		88,225		-
Genlyte Group*		1,963,000		637,000		1,650,000		950,000		90,440		-
Gibraltar Industries		2,860,000		-		-		2,860,000		44,101		715
Glacier Bancorp		4,080,000		166,000		-		4,246,000		79,570		2,021
Helen of Troy		1,800,000		100,000		-		1,900,000		32,566		-
Herman Miller		2,068,000		1,932,000		-		4,000,000		129,560		1,186
Highland Hospitality*		5,850,000		-		5,850,000		-		-		1,346
HNI*		2,550,000		-		550,000		2,000,000		70,120		1,758
ICU Medical		1,083,000		167,000		-		1,250,000		45,013		-
iGate		5,000,000		-		-		5,000,000		42,350		-
II-VI		2,025,000		375,000		-		2,400,000		73,320		-
Interline Brands		-		1,700,000		-		1,700,000		37,247		-
Indus International (merged into Vista Equity)*		5,600,000		-		5,600,000		-		-		-
ITT Educational Services		2,250,000		-		250,000		2,000,000		170,540		-
IXYS		1,905,000		-		-		1,905,000		15,278		-
JDA Software*		1,490,000		-		1,490,000		-		-		-
Kaydon		1,100,000		596,000		-		1,696,000		92,500		693
Kenexa		828,000		1,597,000		-		2,425,000		47,094		-
Kite Realty Group		1,720,000		-		-		1,720,000		26,264		1,359
Knoll		1,809,000		1,591,000		-		3,400,000		55,862		1,180

See accompanying notes to financial statements.

31

Columbia Acorn Fund

Statement of Investments, continued

> Notes to Statement of Investments (dollar values in thousands)

Affiliates	Balance of Shares Held 12/31/06		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/07		Value		Dividend
Kronos (merged into Helman & Friedman)*		2,750,000		-		2,750,000		-	$	-	$	-
LCA-Vision*		1,125,000		-		1,125,000		-		-		608
Littelfuse		1,135,000		285,000		-		1,420,000		46,803		-
Marchex		-		1,700,000		-		1,700,000		18,462		59
Marlin Business Services		685,000		415,000		-		1,100,000		13,266		-
McGrath Rentcorp		1,212,000		488,000		-		1,700,000		43,775		938
Meadowbrook Insurance Group		-		2,000,000		-		2,000,000		18,820		-
Mine Safety Appliances		1,900,000		-		86,000		1,814,000		94,092		1,558
Mobile Mini		1,650,000		100,000		-		1,750,000		32,445		-
Navigant Consulting		1,900,000		600,000		-		2,500,000		34,175		-
Neurogen		655,000		1,645,000		-		2,300,000		7,935		-
Orthofix International		942,500		387,500		-		1,330,000		77,100		-
Oxford Industries		919,000		150,000		-		1,069,000		27,548		743
Pharmacopeia		-		1,675,000		-		1,675,000		7,990		-
Pinnacle Entertainment		3,200,000		850,000		-		4,050,000		95,418		-
Pool		2,500,000		390,000		-		2,890,000		57,309		1,329
Princeton Review		2,550,000		-		-		2,550,000		21,242		-
ProQuest*		2,000,000		-		2,000,000		-		-		-
QLT		2,500,000		1,500,000		-		4,000,000		17,680		-
Quality Systems		-		1,510,000		-		1,510,000		46,040		348
Radiant Systems		2,500,000		-		-		2,500,000		43,075		-
Red Robin Gourmet Burgers		1,000,000		-		-		1,000,000		31,990		-
Saga Communications		1,400,000		-		-		1,400,000		8,246		-
Salem Communications		1,541,000		-		-		1,541,000		10,155		647
Sanmina-SCI		10,000,000		19,500,000		-		29,500,000		53,690		-
Seachange International*		1,875,000		-		1,875,000		-		-		-
Seattle Genetics		2,300,000		1,420,000		-		3,720,000		42,408		-
Shuffle Master		2,430,000		-		-		2,430,000		29,136		-
SkillSoft		9,500,000		-		-		9,500,000		90,820		-
Spanish Broadcasting System		2,400,000		-		-		2,400,000		4,440		-
Spartech*		2,700,000		-		2,700,000		-		-		1,008
Supertex		690,000		340,000		130,000		900,000		28,161		-
Switch & Data Facilities		-		2,000,000		-		2,000,000		32,040		-
Time Warner Telecom		4,500,000		3,500,000		-		8,000,000		162,320		-
TriCo Bancshares		-		900,000		-		900,000		17,370		219
TrueBlue		-		2,300,000		-		2,300,000		33,304		-
Tumbleweed Communications*		3,500,000		-		3,500,000		-		-		-
United America Indemnity*		1,550,000		-		1,550,000		-		-		-
Universal Technical Institute		1,500,000		-		-		1,500,000		25,500		-
Vaalco Energy*		3,200,000		-		450,000		2,750,000		12,787		-
Vail Resorts		2,390,000		-		-		2,390,000		128,606		-
Viad		-		1,453,000		-		1,453,000		45,886		70
Vital Signs		870,000		-		-		870,000		44,474		339
Voyager Learning		-		2,000,000		-		2,000,000		14,300		-
Watsco		2,375,000		-		-		2,375,000		87,305		3,111
West Bancorporation		949,000		363,000		-		1,312,000		17,108		740
West Coast Bancorp		1,320,000		117,000		-		1,437,000		26,584		669
Witness Systems*		2,500,000		-		2,500,000		-		-		-
World Acceptance		1,500,000		175,000		-		1,675,000		45,191		-
TOTAL OF AFFILIATED TRANSACTIONS		230,096,801		76,399,299		57,147,100		249,349,000	$	5,035,542	$	36,575

*  At December 31, 2007, the Fund owned less than five percent or more of the company's outstanding voting shares.

  The aggregate cost and value of these companies at December 31, 2007, was $3,677,369 and $5,035,542 respectively. Investments in affiliate companies represented 25.3% of the Fund's total net assets at December 31, 2007.

See accompanying notes to financial statements.

32

> Notes to Statement of Investments (dollar values in thousands)

(c)  Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued in good faith by the board of trustees. At December 31, 2007, these securities amounted to $1,427 which represented 0.01% of total net assets.

  Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Perlegen Sciences	3/30/01		1,249,999	$	4,500	$	400
Locus Pharmaceuticals, Series A-1 Pfd.	9/5/01		187,500		7,500		488
MicroDose Technologies	11/24/00		359,944		2,005		288
Locus Pharmaceuticals, Series B-1 Pfd.	2/8/07		96,644		280		251
Security Capital European Realty	8/20/98-11/12/99		37,407		205		-
				$	14,490	$	1,427

(d)  Security has no value.

(e)  Security exempt from registration under Section 4(2) of the Securities Act of 1933. These securities may only be resold in exempt transactions to qualified buyers. Private resales of these securities to qualified institutional buyers are also exempt from registration pursuant to Rule 144A under the Securities Act of 1933. At December 31, 2007, these securities had an aggregate value of $512,134, which represented 2.6% of net assets.

(f)  At December 31, 2007, for federal income tax purposes cost of investments was $13,141,866 and net unrealized appreciation was $6,795,790 consisting of gross unrealized appreciation of $7,838,307 and gross unrealized depreciation of $1,042,517.

(g)  On December 31, 2007, the market value of foreign securities represented 11.63% of total net assets. The Fund's foreign portfolio was diversified as follows:

	Value		Percent
Netherlands	$	467,017		2.34	%
Canada		210,890		1.06
Japan		202,524		1.02
France		189,368		0.95
Germany		111,674		0.56
China		110,189		0.55
United Kingdom		103,427		0.52
Sweden		99,911		0.50
India		96,864		0.49
Australia		96,618		0.48
Hong Kong		92,641		0.47
South Africa		69,114		0.35
Denmark		59,818		0.30
	Value		Percent
Mexico	$	50,580		0.25	%
Israel		48,940		0.25
Greece		46,898		0.24
Ireland		46,237		0.23
Switzerland		43,234		0.22
Singapore		36,564		0.18
Chile		34,466		0.17
Austria		26,921		0.14
Taiwan		23,983		0.12
Brazil		22,773		0.11
Spain		14,875		0.07
Italy		11,056		0.06
Luxembourg		-		-
Total Foreign Portfolio	$	2,316,582		11.63	%

See accompanying notes to financial statements.

33

Columbia Acorn International

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	09/30/07		12/31/07
Additions
Europe
> France
Neopost		160,000		280,000
Sperian Protection		190,000		225,000
> Netherlands
SBM Offshore		450,000		475,300
Vopak		0		450,000
> Germany
CTS Eventim		750,000		850,000
Hamburger Hafen und Logistik		0		275,000
MPC Muechmeyer Petersen Capital		330,000		400,000
Rational		140,000		155,000
Vossloh		250,000		300,000
> United Kingdom
Detica		2,375,000		3,000,000
Informa Group		2,400,000		3,000,000
Intertek Testing		1,000,000		1,600,000
> Sweden
Securitas Systems		8,900,000		10,400,000
> Ireland
Grafton Group		1,040,000		1,200,000
Kingspan Group		665,000		845,000
United Drug		8,416,000		8,840,000
> Italy
Cobra Automotive		0		580,000
> Austria
Wienerberger		400,000		549,332
Zumtobel		1,052,000		1,200,000
Asia
> Japan
Casio Computer		0		1,950,000
Hirose Electric		72,000		175,000
OSG		0		1,800,000
Point		200,000		273,000
SYSMEX		440,000		536,000
Topcon		1,300,000		1,700,000
Unicharm PetCare		329,300		373,000
Union Tool		500,000		608,000
Yusen Air & Sea Service		1,344,000		1,580,000
> China
Fu Ji Food & Catering Services		7,500,000		9,300,000
Lenovo Group		48,430,000		55,730,000
Sinotrans		0		30,500,000
VisionChina Media		0		556,500
Xinyu Hengdeli		30,890,000		34,000,000

	Number of Shares
	09/30/07		12/31/07
Asia—continued
> South Korea
JVM		0		116,500
Mirae Asset Securities		0		57,700
Woongjin Coway		977,000		1,192,000
> Hong Kong
Hong Kong Aircraft Engineering		0		700,000
Lifestyle International		10,000,000		12,750,000
> Singapore
ComfortDelGro		17,000,000		20,000,000
OLAM		4,000,000		10,000,000
> Taiwan
Everlight Electronics		3,604,723		7,004,722
Formosa International Hotels		795,826		1,995,826
GeoVision		0		1,500,000
Other Countries
> United States
Decode Genetics		0		1,135,000
Tesco		379,239		450,000
> Australia
Australian Stock Exchange		750,000		850,000
Sino Gold		5,480,000		5,843,650
> South Africa
Mr. Price		4,460,000		7,600,000
> Canada
CCL		0		127,100
> New Zealand
Sky City Entertainment		5,773,789		5,932,812
Latin America
> Brazil
BM&F		0		1,010,100
Bovespa		0		2,000,000
Localiza Rent A Car		2,000,000		3,000,000
> Mexico
Financiera Independencia		0		6,000,000
Megacable		0		4,000,000

See accompanying notes to financial statements.

34

	Number of Shares
	09/30/07		12/31/07
Sales
Europe
> France
Carbone Lorraine		600,000		534,000
> Netherlands
USG People		705,000		410,000
> Germany
Deutsche Boerse		250,000		125,000
> Switzerland
Nobel Biocare Holding		165,000		110,000
Synthes		360,000		300,000
> United Kingdom
BBA Group		3,007,000		0
Tullow Oil		3,255,691		1,798,000
> Russia
RosBusinessConsulting		486,000		473,671
> Poland
Central European Distribution		1,125,500		830,000
Asia
> Japan
Ito En		718,000		500,000
Nagaileben		123,900		64,000
USS		430,000		293,000
> China
China Shipping Development		23,547,000		21,318,000
> South Korea
Taewoong		444,000		337,000
> Hong Kong
Hong Kong Exchanges and Clearing		4,000,000		2,500,000
> India
Housing Development Finance		1,300,000		1,000,000
> Taiwan
Advantech		7,306,757		4,145,000

	Number of Shares
	09/30/07		12/31/07
Other Countries
> United States
Atwood Oceanics		865,000		725,000
> Canada
Talisman Energy		865,000		0
Latin America
> Brazil
Natura Cosmeticos		2,500,000		1,500,000
> Mexico
Consorcio ARA		18,000,000		0

See accompanying notes to financial statements.

35

Columbia Acorn International

Statement of Investments, December 31, 2007

Number of Shares			Value (000)
				Equities: 95.2%
Europe 49.4%
		> France 8.6%
	3,000,000	SES Global	$	78,666
		Satellite Broadcasting Services
	500,000	Iliad		53,417
		Alternative Internet & Telecoms Provider
	375,000	Norbert Dentressangle		39,157
		Transport
	380,000	Rubis		37,077
		Tank Storage & LPG Supplier
	534,000	Carbone Lorraine		36,796
		Advanced Industrial Materials
	280,000	Neopost		28,752
		Postage Meter Machines
	206,000	Pierre & Vacances		28,460
		Vacation Apartment Lets
	656,700	Trigano		28,362
		Leisure Vehicles & Camping Equipment
	240,000	Eurofins Scientific		27,812
		Food Screening & Testing
	225,000	Sperian Protection		25,590
		Safety Equipment
	700,000	Legrand		23,776
		Electrical Components
	350,000	April Group		23,495
		Insurance Policy Construction
	251,000	Imerys		20,554
		Industrial Minerals Producer
	410,000	Meetic (a)		17,905
		Dating Services
	100,000	Ciments Francais		17,121
		Leading French & Emerging Markets Cement Producer
	1,100,000	Hi-Media		9,683
		Leading Online Advertiser in Europe
				496,623
		> Netherlands 8.0%
	1,406,155	Fugro		107,783
		Oilfield Services
	686,800	Smit Internationale		69,933
		Harbor & Offshore Towage & Marine Services
	1,385,000	Unit 4 Agresso (b)		39,345
		Business & Security Software
	1,947,042	Aalberts Industries		38,377
		Flow Control & Heat Treatment
	1,437,000	Imtech		35,317
		Engineering & Technical Services
	1,096,000	Koninklijke TenCate		33,878
		Advanced Textiles & Industrial Fabrics
	489,000	Boskalis Westminster		29,706
		Dredging & Maritime Contractor
	450,000	Vopak		25,454
		World's Largerst Operator of Petroleum & Chemical Storage Terminals
	833,000	OPG Groep		23,015
		Health Care Supplies & Pharmacies
	1,525,000	Wavin		20,172
		Largest European Plastic Pipe Systems Company

Number of Shares			Value (000)
	800,000	QIAGEN (a)	$	17,181
		Life Science Company; DNA/RNA Purification
	475,300	SBM Offshore		14,909
		Builds & Leases Offshore Vessels to Process & Store Crude Oil
	410,000	USG People		10,991
		Temporary Staffing Services
				466,061
		> Germany 6.7%
	1,800,000	Rhoen-Klinikum		56,296
		Health Care Services
	500,000	Wincor Nixdorf		47,119
		Retail POS Systems & ATM Machines
	310,987	Elringklinger		38,647
		Automobile Components
	400,000	MPC Muechmeyer Petersen Capital		35,507
		Alternative Asset Manager
	300,000	Vossloh		35,080
		Rail Infrastructure & Diesel Locomotives
	850,000	CTS Eventim		32,670
		Event Ticket Sales
	155,000	Rational		31,711
		Commercial Oven Manufacturer
	125,000	Deutsche Boerse		24,673
		Trading, Clearing, Settlement Services for Financial Markets
	275,000	Hamburger Hafen und Logistik (a)		24,526
		Terminal Operator at the Hamburg Port
	525,000	GFK		21,026
		Market Research Services
	918,000	Takkt		15,955
		Mail Order Retailer of Office & Warehouse Durables
	7,500	Porsche		15,114
		Specialty Automobile Manufacturer
	354,500	Deutsche Beteiligungs		11,088
		Private Equity Investment Management
				389,412
		> Switzerland 5.4%
	600,000	Kuehne & Nagel		57,203
		Freight Forwarding/Logistics
	140,000	Burckhardt Compression		45,243
		Gas Compression Pumps
	24,000	Sika		45,114
		Chemicals for Construction & Industrial Applications
	300,000	Synthes		37,082
		Products for Orthopedic Surgery
	250,000	Geberit		34,083
		Plumbing Supplies
	110,000	Nobel Biocare Holding		29,099
		Dental Implants & Ceramic Crowns
	450,000	Schindler		28,766
		Elevator Manufacturer & Service Provider
	25,000	Givaudan		24,020
		Fragrances & Flavors
	400,000	Logitech International (a)		14,523
		Branded Peripheral Computer Devices
				315,133

See accompanying notes to financial statements.

36

Number of Shares			Value (000)
		> United Kingdom 5.4%
	1,970,714	Expro International Group	$	40,197
		Offshore Oilfield Services
	2,500,000	Northgate		38,009
		Light Commercial Vehicle Rental Specialist
	3,000,000	Smith & Nephew		34,491
		Medical Equipment & Supplies
	1,600,000	Intertek Testing		31,370
		Testing, Inspection, Certification Services
	7,000,000	Taylor Nelson Sofres		28,684
		Market Research
	3,000,000	Informa Group		27,441
		Global Publisher & Event Organizer
	4,230,000	RPS Group		26,806
		Environmental Consulting & Planning
	640,000	Randgold Resources		23,763
		Gold Mining in Western Africa
	1,798,000	Tullow Oil		23,199
		Oil & Gas Producer
	1,002,000	Rotork		19,177
		Valve Actuators for Oil & Water Pipelines
	3,000,000	Detica		13,082
		UK IT Services Company
	650,000	Keller Group		8,504
		International Ground Engineering Specialist
				314,723
		> Sweden 2.9%
	3,960,000	Hexagon		81,661
		Measurement Equipment & Polymers
	10,400,000	Securitas Systems		36,691
		Commercial Security Installation & Service
	3,135,000	SWECO		31,359
		Engineering Consultants
	2,265,000	Nobia		20,083
		Kitchen Cabinet Manufacturing & Distribution
				169,794
		> Ireland 2.3%
	8,840,000	United Drug		50,975
		Irish Pharmaceutical Wholesaler & Outsourcer
	1,800,000	IAWS Group		39,844
		Baked Goods
	600,000	Paddy Power		19,739
		Irish Betting Services
	845,000	Kingspan Group		12,735
		Building Insulation & Environmental Containers
	1,200,000	Grafton Group (a)		9,431
		Builders Materials Wholesaling & Do-it-yourself Retailing
				132,724
		> Italy 1.9%
	9,100,000	CIR		33,430
		Italian Holding Company
	12,531,048	Ducati Motor (a)		25,608
		Motorcycles & Related Merchandise
	3,750,000	Amplifon		18,924
		Hearing Aid Retailer
	1,243,000	GranitiFiandre		15,809
		Innovative Stoneware

Number of Shares			Value (000)
	375,000	Sabaf	$	12,117
		Supplier to White Goods Original Equipment Manufacturer
	580,000	Cobra Automotive (a)		5,379
		Electronic Car Theft Protection
				111,267
		> Greece 1.3%
	3,790,000	Intralot		74,681
		Lottery & Gaming Systems & Services
				74,681
		> Austria 1.3%
	1,200,000	Zumtobel		43,074
		Lighting Systems
	549,332	Wienerberger		30,345
		Bricks & Clay Roofing Tiles
				73,419
		> Spain 1.2%
	400,000	Red Electrica de Espana		25,138
		Spanish Power Grid
	600,000	Sogecable (a)		23,906
		Spain's Main Pay-TV
	1,050,000	Prisa		19,523
		Leading Spanish-speaking Publisher
				68,567
		> Finland 1.0%
	1,756,000	Poyry		44,107
		Engineering Consultants
	354,000	Stockmann		15,247
		Department Stores in Finland, Baltics & Russia
				59,354
		> Russia 0.9%
	775,000	Novolipetsk Steel (a)		31,698
		Vertically Integrated Steel Producer
	473,671	RosBusinessConsulting		19,610
		Financial Information, Media & IT Services in Russia
				51,308
		> Poland 0.8%
	830,000	Central European Distribution (a)		48,206
		Vodka Production & Alcohol Distribution
				48,206
		> Czech Republic 0.8%
	183,000	Komercni Banka		44,034
		Leading Czech Universal Bank
				44,034
		> Denmark 0.5%
	265,000	Novozymes		29,909
		Industrial Enzymes
				29,909
		> Norway 0.4%
	2,774,800	Kongsberg Automotive (b)		20,388
		Automotive Seating & Component Supplier
				20,388
Europe: Total				2,865,603

See accompanying notes to financial statements.

37

Columbia Acorn International

Statement of Investments, continued

Number of Shares			Value (000)
Asia 29.4%
		> Japan 13.1%
	730,000	Ibiden	$	50,422
		Electronic Parts & Ceramics
	6,000,000	Kansai Paint		43,521
		Paint Producer in Japan, India, China & Southeast Asia
	1,700,000	Ushio		37,312
		Industrial Light Sources
	43,500	Jupiter Telecommunications (a)		36,799
		Largest Cable Service Provider in Japan
	1,580,000	Yusen Air & Sea Service		35,783
		Airfreight Logistics
	1,080,000	Hoya		34,468
		Opto-electrical Components & Eyeglass Lenses
	4,000,000	Park24		30,804
		Parking Lot Operator
	18,000	Kenedix		28,963
		Real Estate Investment Management
	816,200	Kintetsu World Express		28,244
		Airfreight Logistics
	885,000	Aeon Mall		23,230
		Suburban Shopping Mall Developer, Owner & Operator
	536,000	SYSMEX		22,737
		In Vitro Diagnostics (IVD) Equipment & Reagent Manufacturer
	1,950,000	Casio Computer		22,695
		Micro-consumer Electronic Goods
	10,000	Risa Partners		21,879
		NPL & Real Estate Related Investment
	1,150,000	FCC		20,462
		Auto/Motorcycle Clutches
	175,000	Hirose Electric		20,275
		Electrical Connectors
	608,000	Union Tool		20,110
		Precision Drill Bit Manufacturer
	1,600,000	Cosel		19,862
		Industrial Standard Switching Power Supply System
	1,800,000	OSG		19,690
		Consumable Cutting Tools
	373,000	Unicharm PetCare		19,328
		Pet Food & Pet Toiletries
	6,000,000	Kansai Urban Banking		18,881
		Regional Bank
	145,000	Nakanishi		18,742
		Dental Tools & Machinery
	293,000	USS		18,178
		Used Car Auctioneer
	700,000	As One		16,447
		Scientific Supplies Distributor
	1,700,000	Topcon		15,998
		Positioning & Medical Instrument
	965,000	T. Hasegawa		15,141
		Industrial Flavors & Fragrances
	273,000	Point		13,870
		Apparel Specialty Retailer
	2,300,000	Bank of Fukuoka		13,718
		Regional Bank

Number of Shares			Value (000)
	2,400	Osaka Securities Exchange	$	11,176
		Osaka Securities Exchange
	380,000	Takata		11,035
		Safety Related Auto Parts
	500,000	Ito En		9,520
	215,400	Ito En, Pfd.		3,072
		Bottled Tea & Other Beverages
	643,000	Ain Pharmaciez (b)		9,329
		Dispensing Pharmacy/Drugstore Operator
	506,000	Aeon Delight		9,247
		Facility Maintenance & Management
	1,230,000	Kamigumi		8,888
		Port Cargo Handling & Logistics
	4,000	Wacom		8,338
		Computer Graphic Illustration Devices
	14,000	FullCast (b)		8,192
		Employment Outsourcing
	1,650	Japan Pure Chemical		6,166
		Precious Metal Plating Chemicals for Electronics
	2,900	Message		5,646
		Nursing Care Facility Operator
	64,000	Nagaileben		1,114
		Medical/Health Care Related Clothes
				759,282
		> China 5.2%
	21,318,000	China Shipping Development		55,594
		China's Dominant Shipper for Oil & Coal
	55,730,000	Lenovo Group		49,275
		Third Largest PC Vendor Globally
	29,648,000	China Green		31,534
		Agricultural Grower & Processor in China
	26,508,000	Jiangsu Expressway		28,606
		Chinese Toll Road Operator
	20,910,000	Travelsky Technology		22,034
		Online Air Travel Bookings in China
	400,000	Sohu.com (a)		21,808
		Advertising on Chinese Internet Portal
	25,000,000	Hopewell Highway Infrastructure		21,425
		Guangdong Tollroad Leading to Hong Kong & Macau
	9,300,000	Fu Ji Food & Catering Services		21,330
		Food Catering Service Provider in China
	34,000,000	Xinyu Hengdeli		19,070
		A High-end Watch Retailer in China
	21,750,000	TPV Technology		15,716
		Original Design Manufacturer for LCD Monitor & Flat TV
	30,500,000	Sinotrans		13,325
		Largest Integrated Logistics Player in China
	556,500	VisionChina Media (a)		4,730
		Advertising on Digital Screens in China's Mass Transit System
				304,447
		> South Korea 2.8%
	154,301	MegaStudy		43,685
		Online Education Service Provider
	1,192,000	Woongjin Coway		38,403
		South Korean Household Appliance Rental Service Provider

See accompanying notes to financial statements.

38

Number of Shares			Value (000)
		> South Korea—continued
	337,000	Taewoong	$	31,631
		A Player in the Niche Customized Forging Market
	915,000	Sung Kwang Bend		26,261
		A Large Customized Industrial Pipe Fitting Manufacturer
	57,700	Mirae Asset Securities		10,402
		Korean Largest Diversified Financial Company
	116,500	JVM (a)		7,008
		Automatic Tablet Dispensing & Packaging Systems
	262,000	YBM Sisa.com		4,159
		Online Language Educator & Tester
				161,549
		> Hong Kong 2.3%
	2,500,000	Hong Kong Exchanges and Clearing		70,182
		Hong Kong Equity & Derivatives Market Operator
	12,750,000	Lifestyle International		34,312
		Mid to High-end Department Store Operator in Hong Kong & China
	700,000	Hong Kong Aircraft Engineering		18,883
		Aircraft Maintenance, Repair, Overhaul Operator
	46,000,000	Global Digital Creations (a)		9,971
		Digital Cinema Solution Provider/ Network Operator
				133,348
		> India 2.3%
	1,000,000	Housing Development Finance		71,751
		Indian Mortgage Lender
	4,450,000	United Phosphorus		39,419
		Off-patent Crop Protection Chemicals
	700,000	Asian Paints		19,438
		India's Largest Paint Company
	40,705	JSW Steel		1,354
		Flat Steel Producer in India
				131,962
		> Singapore 1.9%
	7,000,000	Singapore Exchange		63,987
		Singapore Equity & Derivatives Market Operator
	20,000,000	ComfortDelGro		25,164
		Taxi & Mass Transit Service
	10,000,000	OLAM		19,658
		Agriculture Supply Chain Manager
				108,809
		> Taiwan 1.4%
	7,004,722	Everlight Electronics		25,486
		Led Packager
	1,995,826	Formosa International Hotels		17,906
		Hotel, Food & Beverage Operation & Hospitality Management Services
	7,501,588	Wah Lee Industrial		14,273
		Distributor of Chemicals, Materials & Equipment
	1,500,000	GeoVision		13,729
		Taiwan PC-based Video Surveillance Player
	4,145,000	Advantech		9,400
		Embedded Computers
				80,794

Number of Shares			Value (000)
		> Indonesia 0.4%
	15,000,000	Perusahaan Gas Negara	$	24,288
		Gas Pipeline Operator
				24,288
Asia: Total				1,704,479
Other Countries 11.0%
		> Australia 3.2%
	850,000	Australian Stock Exchange		44,944
		Australian Equity & Derivatives Market Operator
	2,000,000	Jubilee Mines		39,750
		Nickel Mining in Australia
	3,000,000	Billabong International		38,982
		Action Sports Apparel Brand Manager
	5,843,650	Sino Gold (a)		35,364
		Gold Mining in The People's Republic of China
	475,000	Perpetual Trustees		27,661
		Mutual Fund Management
				186,701
		> United States 3.0%
	725,000	Atwood Oceanics (a)		72,674
		Offshore Drilling Contractor
	758,000	FMC Technologies (a)		42,979
		Oil & Gas Wellhead Manufacturer
	565,000	Dresser-Rand Group (a)		22,063
		Largest Manufacturer of Compressors
	600,000	BioMarin (a)		21,240
		Biotech Focused on Orphan Diseases
	450,000	Tesco (a)		12,901
		Developing New Well Drilling Technologies
	1,135,000	Decode Genetics (a)		4,177
		Drugs for Heart Attack, Asthma & Vascular Disease
				176,034
		> South Africa 2.6%
	1,440,000	Impala Platinum Holdings		49,678
		Platinum Group Metals Mining & Refining
	4,299,000	Uranium On (a)		38,462
		Uranium Mines in South Africa, Kazakhstan, Australia & the U.S.
	1,560,000	Naspers		36,721
		Media & Education in Africa & other Emerging Markets
	7,600,000	Mr. Price		24,444
		South African Retailer of Apparel, Household Goods & Sporting Goods
				149,305
		> Canada 1.8%
	1,860,000	ShawCor		66,602
		Oil & Gas Pipeline Products
	1,333,000	RONA (a)		23,028
		Leading Canadian Do-it-yourself Retailer
	850,000	Ivanhoe Mines (a)		9,301
		Copper Mine Project in Mongolia

See accompanying notes to financial statements.

39

Columbia Acorn International

Statement of Investments, continued

Number of Shares			Value (000)
		> Canada—continued
	127,100	CCL	$	4,972
		Leading Global Label Manufacturer
				103,903
		> New Zealand 0.4%
	5,932,812	Sky City Entertainment		21,002
		Casino/Entertainment Complex
				21,002
Other Countries: Total				636,945
Latin America 5.4%
		> Brazil 3.5%
	4,300,000	Suzano		69,650
		Brazilian Pulp & Paper Producer
	2,000,000	Bovespa (a)		38,539
		Brazil Equity & Derivative Exchange
	3,000,000	Localiza Rent A Car		31,545
		Car Rental
	800,000	Porto Seguro		29,365
		Auto & Life Insurance
	1,500,000	Natura Cosmeticos		14,195
		Direct Retailer of Cosmetics
	1,010,100	BM&F (a)		14,187
		Brazilian Derivatives Exchange
	520,800	Redecard		8,338
		Credit/Debit Card Acquirer/Processor
				205,819
		> Mexico 1.4%
	500,000	Grupo Aeroportuario del Surest		30,610
		Cancun & Cozumel Airport Operator
	7,000,000	Urbi Desarrollos Urbanos (a)		24,179
		Affordable Housing Builder
	4,000,000	Megacable (a)		13,582
		Mexican Cable & Internet Operator
	6,000,000	Financiera Independencia (a)		10,302
		Mexican Micro-finance Lender
				78,673
		> Chile 0.5%
	160,000	Sociedad Quimica y Minera de Chile		28,280
		Producer of Specialty Fertilizers, Lithium & Iodine
				28,280
Latin America: Total				312,772
Total Equities: 95.2% (Cost: $3,666,829)				5,519,799

Principal Amount (000)			Value (000)
Short-Term Obligations 5.4%
$	30,400	United Parcel Service (c) 4.22% Due 1/16/08	$	30,346
	30,300	IBM International Group (c) 4.39% Due 1/02/08		30,296
	29,000	Emerson Electric (c) 4.20% Due 1/02/08		28,997
	29,000	General Electric Capital 4.15% Due 1/04/08		28,990
	28,600	Toyota Motor Credit 4.15% Due 1/03/08		28,593
	28,100	Hershey Foods (c) 4.22% Due 1/02/08		28,097
	27,900	Nestle Capital (c) 4.24% Due 1/08/08		27,877
	27,700	Chevron Funding 4.21% Due 1/02/08		27,697
	79,722	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by U.S. Government Agency Obligations with various maturities to 5/28/18, market value $81,329 (repurchase proceeds $79,735)		79,722
		(Amortized Cost: $310,615)		310,615
Total Investments: 100.6% (Cost: $3,977,444)(d)(e)				5,830,414
Cash and Other Assets Less Liabilities: (0.6)%				(32,086	)
Total Net Assets: 100%			$	5,798,328

See accompanying notes to financial statements.

40

> Notes to Statement of Investments (dollar values in thousands)

(a)  Non-income producing security.

(b)  An affiliate may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in these affiliated companies during the twelve months ended December 31, 2007, are as follows:

Affiliates	Balance of Shares Held 12/31/06		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/07		Value		Dividend
AIN Pharmaciez		643,000		-		-		643,000	$	9,329	$	91
FullCast		-		14,000		-		14,000		8,192		226
Kongsberg Automotive		2,065,000		709,800		-		2,774,800		20,388		386
Unit 4 Agresso		1,150,000		235,000		-		1,385,000		39,345		1,194
Van Houtte*		950,000		-		950,000		-		-		245
TOTAL OF AFFILIATED TRANSACTIONS		4,808,000		958,800		950,000		4,816,800	$	77,254	$	2,142

*  At December 31, 2007, the Fund owned less than five percent of the company's outstanding voting shares.

  The aggregate cost and value of these companies at December 31, 2007, was $89,822 and $77,254 respectively. Investments in affiliate companies represented 1.33% of total net assets at December 31, 2007.

(c)  Security exempt from registration under Section 4(2) of the Securities Act of 1933. These securities may only be resold in exempt transactions to qualified buyers. Private resales of these securities to qualified institutional buyers are also exempt from registration pursuant to Rule 144A under the Securities Act of 1933. At December 31, 2007, these securities had an aggregate value of $145,613, which represented 2.5% of net assets.

(d)  At December 31, 2007, for federal income tax purposes cost of investments was $3,979,936 and net unrealized appreciation was $1,850,478 consisting of gross unrealized appreciation of $2,094,574 and gross unrealized depreciation of $244,096.

(e)  On December 31, 2007, the Fund's total investments were denominated in currencies as follows:

Currency	Value		% of Total Net Assets
Euro	$	1,872,108		32.3	%
Japanese Yen		759,282		13.1
US Dollar		695,355		12.0
Hong Kong Dollar		411,256		7.1
Swiss Franc		315,133		5.4
British Pound		290,960		5.0
Other currencies less than 5% of total net assets		1,486,320		25.7
	$	5,830,414		100.6	%

See accompanying notes to financial statements.

41

Columbia Acorn International

Portfolio Diversification

At December 31, 2007, the Fund's portfolio investments as a percent of net assets were diversified as follows:

	Value (000)		Percent
> Industrial Goods & Services
Industrial Materials & Specialty Chemicals	$	432,819		7.5	%
Other Industrial Services		413,441		7.1
Machinery		276,397		4.8
Conglomerates		203,890		3.5
Electrical Components		144,299		2.5
Outsourcing Services		132,424		2.3
Construction		102,788		1.8
Steel		33,052		0.6
Industrial Distribution		25,878		0.4
		1,764,988		30.5
> Consumer Goods & Services
Other Consumer Services		197,728		3.4
Retail		131,895		2.2
Casinos & Gaming		115,422		2.0
Food & Beverage		105,300		1.8
Other Durable Goods		89,715		1.5
Consumer Goods Distribution		66,384		1.1
Apparel		54,229		1.0
Travel		53,579		0.9
Other Entertainment		50,576		0.9
Nondurables		38,495		0.7
Consumer Electronics		38,411		0.7
Leisure Products		38,333		0.7
Furniture & Textiles		20,083		0.3
		1,000,150		17.2
> Information
Financial Processors		158,842		2.7
Computer Hardware & Related Equipment		128,655		2.2
Satellite Broadcasting & Services		78,666		1.4
Business Information & Marketing Services		76,516		1.3
Internet Related		75,225		1.3
CATV		74,287		1.3
Semiconductors & Related Equipment		59,954		1.0
Publishing		46,964		0.8
Business Software		39,345		0.7
TV Broadcasting		36,721		0.6
Computer Services		32,692		0.6
Instrumentation		15,998		0.3
Advertising		14,413		0.3
Electronics Distribution		14,273		0.2
		852,551		14.7

	Value (000)			Percent
> Energy & Minerals
Oil Services	$	409,814			7.1	%
Mining		196,318			3.4
Oil Refining, Marketing & Distribution		86,819			1.5
Agricultural Commodities		69,650			1.2
Oil & Gas Producers		23,199			0.4
		785,800			13.6
> Finance
Brokerage & Money Management		146,821			2.5
Banks		76,633			1.3
Savings & Loans		71,751			1.3
Insurance		52,860			0.9
Closed End Funds		35,507			0.6
Finance Companies		21,478			0.4
Credit Cards		8,338			0.1
		413,388			7.1
> Other Industries
Transportation		292,702			5.1
Real Estate		75,021			1.3
Regulated Utilities		25,138			0.4
		392,861			6.8
> Health Care
Medical Equipment & Devices		130,417			2.2
Health Care Services		84,957			1.5
Pharmaceuticals		50,975			0.9
Biotechnology & Drug Delivery		25,417			0.4
Medical Supplies		18,295			0.3
		310,061			5.3
Total Equities:		5,519,799			95.2
Short-Term Obligations:		310,615			5.4
Total Investments:		5,830,414			100.6
Cash and Other Assets Less Liabilities:		(32,086	)		(0.6	)
Net Assets:	$	5,798,328			100.0	%

See accompanying notes to financial statements.

42

Columbia Acorn USA

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	09/30/07		12/31/07
Additions
Information
AMIS Holdings		762,300		900,000
Blackbaud		386,406		525,000
Ciena		85,000		125,000
Cogent Communications		0		223,100
Global Payments		393,280		468,280
Informatica		370,000		570,000
IPG Photonics		192,906		425,000
Netgear		97,300		190,000
Plexus		0		115,000
Scientific Games		0		100,000
SRA International		95,000		205,000
Varian		0		45,000
Viad		0		100,000
Consumer Goods & Services
Herman Miller		0		175,000
Thor Industries		80,000		180,000
True Religion Apparel		885,200		950,313
Winnebago		0		150,000
Industrial Goods & Services
Albany International		0		90,000
American Reprographics		196,000		396,000
Donaldson		319,800		394,800
G&K Services		89,000		179,000
Texas Industries		0		50,000
TrueBlue		0		350,000
Vulcan Materials		0		23,589
Health Care
Alexion Pharmaceuticals		0		40,000
Cephalon		50,000		145,000
Illumina		55,000		85,000
Orthofix International		0		111,360
PSS World Medical		470,000		660,000
Energy & Minerals
Carrizo Oil & Gas		245,000		311,193
Finance
Associated Banc-Corp		98,600		213,600
H & E Equipment Services		0		175,000
Lakeland Financial		164,388		289,698
Marlin Business Services		0		100,000
MB Financial		105,000		205,000
Old Second Bancorp		135,000		220,000
Valley National Bancorp		0		108,300
Other Industries
Rush Enterprises		0		177,353

	Number of Shares
	09/30/07		12/31/07
Sales
Information
Ceridian		350,000		0
Discovery Holding		240,000		0
Windstream		240,000		0
Consumer Goods & Services
Scotts Miracle-Gro		531,400		266,000
Industrial Goods & Services
Florida Rock		204,050		0
Genlyte Group		500,000		0
Goodman Global		272,000		0
Labor Ready		350,000		0
Health Care
Edwards Lifesciences		577,400		115,405
LCA-Vision		210,000		0
Medarex		400,000		320,000
Medicis Pharmaceutical		305,000		180,000
Medicure		3,690,300		2,824,700
MGI Pharma		270,000		0
Myriad Genetics		125,000		100,000
Vital Signs		105,000		50,000
Energy & Minerals
Atwood Oceanics		367,000		330,000
Finance
Greene County Bancshares		145,000		130,000
TCF Financial		179,500		149,800
Thomas Weisel Partners Group		189,523		110,923
United America Indemnity		91,000		0
Other Industries
Northeast Utilities		97,500		0

See accompanying notes to financial statements.

43

Columbia Acorn USA

Statement of Investments, December 31, 2007

Number of Shares			Value (000)
				Equities: 99.1%
Information 33.9%
		> Business Software 6.6%
	340,700	Micros Systems (a)	$	23,904
		Information Systems for Restaurants & Hotels
	779,900	Avid Technology (a)		22,102
		Digital Nonlinear Editing Software & Systems
	525,000	Blackbaud		14,721
		Software & Services for Non-profits
	2,100,000	Novell (a)		14,427
		Directory, Operating System & Identity Management Software
	570,000	Informatica (a)		10,271
		Enterprise Data Integration Software
	215,100	ANSYS (a)		8,918
		Simulation Software for Engineers & Designers
	230,400	Concur Technologies (a)		8,343
		Web Enabled Cost & Expense Management Software
				102,686
		> Instrumentation 4.3%
	860,000	Flir Systems (a)		26,918
		Infrared Cameras
	140,000	Mettler Toledo (a)		15,932
		Laboratory Equipment
	368,000	Trimble Navigation (a)		11,128
		GPS-based Instruments
	425,000	IPG Photonics (a)		8,496
		Fiber Lasers
	45,000	Varian (a)		2,938
		Analytical Instruments
	60,000	FARO Technologies (a)		1,631
		Precision Measurement Equipment
				67,043
		> Mobile Communications 4.1%
	1,005,000	Crown Castle International (a)		41,808
		Communications Towers
	506,000	American Tower (a)		21,556
		Communications Towers in USA & Mexico
	88,000	Globalstar (a)		704
		Satellite Mobile Voice & Data Carrier
				64,068
		> Computer Hardware & Related Equipment 4.1%
	505,000	II-VI (a)		15,428
		Laser Components
	433,581	Nice Systems (Israel) (a)		14,881
		Audio & Video Recording Solutions
	295,600	Amphenol		13,707
		Electronic Connectors
	160,000	Belden CDT		7,120
		Specialty Cable
	190,000	Netgear (a)		6,777
		Networking Products for Small Business & Home
	99,000	Zebra Technologies (a)		3,435
		Bar Code Printers

Number of Shares			Value (000)
	65,000	Intermec (a)	$	1,320
		Bar Code & Wireless LAN Systems
	26,000	Rogers (a)		1,128
		PCB Laminates & High-performance Foams
				63,796
		> Semiconductors & Related Equipment 3.7%
	710,000	Microsemi (a)		15,719
		Analog/Mixed-signal Semiconductors
	1,298,490	Integrated Device Technology (a)		14,686
		Communications Semiconductors
	900,000	AMIS Holdings (a)		9,018
		Mixed-signal Semiconductors
	190,000	Littelfuse (a)		6,262
		Little Fuses
	725,000	Entegris (a)		6,257
		Semiconductor Wafer Shipping & Handling Products
	189,296	Supertex (a)		5,923
		Mixed-signal Semiconductors
				57,865
		> Telecommunications Equipment 2.3%
	2,688,200	Tellabs (a)		17,581
		Telecommunications Equipment
	525,000	Polycom (a)		14,584
		Video Conferencing Equipment
	125,000	Ciena (a)		4,264
		Optical Transport & Broadband Access Equipment
				36,429
		> Telephone Services 2.3%
	1,486,000	Time Warner Telecom (a)		30,151
		Fiber Optic Telephone/Data Services
	223,100	Cogent Communications (a)		5,290
		Internet Data Pipelines
				35,441
		> Internet Related 1.9%
	650,000	TheStreet.com		10,348
		Financial Information Website Publisher
	460,000	ValueClick (a)		10,074
		Internet Advertising
	980,000	CNET Networks (a)		8,957
		Internet Advertising on Niche Websites
				29,379
		> Financial Processors 1.4%
	468,280	Global Payments		21,784
		Credit Card Processor
				21,784
		> Computer Services 1.1%
	205,000	SRA International (a)		6,037
		Government IT Services
	1,005,500	AnswerThink		4,867
		IT Integration & Best Practice Research
	786,000	RCM Technologies (a)(b)		4,622
		Technology & Engineering Services
	235,000	iGate (a)		1,990
		IT & Business Process Outsourcing Services
				17,516

See accompanying notes to financial statements.

44

Number of Shares			Value (000)
		> TV Broadcasting 0.5%
	1,125,000	Entravision Communications (a)	$	8,809
		Spanish Language TV, Radio & Outdoor
				8,809
		> Television Programming 0.4%
	750,000	Lions Gate Entertainment (a)		7,065
		Film & TV Studio
				7,065
		> Radio 0.4%
	511,100	Salem Communications		3,368
		Radio Stations for Religious Programming
	300,000	Saga Communications (a)		1,767
		Radio Stations in Small- & Mid-sized Cities
	705,500	Spanish Broadcasting System (a)		1,305
		Spanish Language Radio Stations
				6,440
		> Gaming Equipment & Services 0.3%
	100,000	Scientific Games (a)		3,325
		Lottery Services Provider
	98,500	Shuffle Master (a)		1,181
		Card Shufflers & Casino Games
				4,506
		> Business Information & Marketing Services 0.3%
	100,000	Viad		3,158
		Trade Show Services, Travel & Tours
	98,300	Navigant Consulting (a)		1,344
		Financial Consulting Firm
				4,502
		> Contract Manufacturing 0.2%
	115,000	Plexus (a)		3,020
		Electronic Manufacturing Services
				3,020
Information: Total				530,349
Consumer Goods & Services 18.1%
		> Retail 4.7%
	398,000	Abercrombie & Fitch		31,828
		Teen Apparel Retailer
	540,000	Urban Outfitters (a)		14,720
		Apparel & Home Specialty Retailer
	175,000	J Crew Group (a)		8,437
		Multi-channel Branded Retailer
	224,500	AnnTaylor Stores (a)		5,738
		Women's Apparel Retailer
	486,250	Christopher & Banks		5,568
		Women's Apparel Retailer
	418,000	Chico's FAS (a)		3,775
		Women's Specialty Retailer
	95,000	Genesco (a)		3,591
		Multi-concept Branded Footwear Retailer
	3,800	Lululemon Athletica (a)		180
		Premium Active Apparel Retailer
				73,837
		> Apparel 2.8%
	950,313	True Religion Apparel (a)		20,289
		Premium Denim

Number of Shares			Value (000)
	634,200	Oxford Industries	$	16,343
		Branded & Private Label Apparel
	222,200	Coach (a)		6,795
		Designer & Retailer of Branded Leather Accessories
				43,427
		> Other Consumer Services 2.8%
	366,000	ITT Educational Services (a)		31,209
		Post-secondary Degree Services
	310,000	Universal Technical Institute (a)		5,270
		Vocational Training
	149,000	NutriSystem (a)		4,020
		Weight Loss Programs
	60,000	Weight Watchers International		2,711
		Weight Loss Programs
				43,210
		> Other Durable Goods 1.9%
	2,078,300	Champion Enterprises (a)		19,578
		Manufactured Homes
	287,900	Cavco Industries (a)		9,742
		Higher End Manufactured Homes
				29,320
		> Leisure Products 1.8%
	301,300	International Speedway		12,408
		Largest Motorsports Racetrack Owner & Operator
	180,000	Thor Industries		6,842
		RV & Bus Manufacturer
	195,500	Speedway Motorsports		6,076
		Motorsports Racetrack Owner & Operator
	150,000	Winnebago		3,153
		Premier Motorhome Maker
				28,479
		> Restaurants 0.8%
	337,500	Sonic (a)		7,391
		Quick Service Restaurant
	163,800	Red Robin Gourmet Burgers (a)		5,240
		Casual Dining Restaurant
				12,631
		> Nondurables 0.8%
	266,000	Scotts Miracle-Gro		9,954
		Consumer Lawn & Garden Products
	108,000	Jarden (a)		2,550
		Branded Household Products
				12,504
		> Furniture & Textiles 0.8%
	400,000	Knoll		6,572
		Office Furniture
	175,000	Herman Miller		5,668
		Office Furniture
				12,240
		> Casinos & Gaming 0.7%
	455,000	Pinnacle Entertainment (a)		10,720
		Regional Casino Operator
				10,720

See accompanying notes to financial statements.

45

Columbia Acorn USA

Statement of Investments, continued

Number of Shares			Value (000)
		> Consumer Goods Distribution 0.7%
	523,500	Pool	$	10,381
		Distributor of Swimming Pool Supplies & Equipment
				10,381
		> Food & Beverage 0.2%
	90,000	Hansen Natural (a)		3,986
		Alternative Beverages
				3,986
		> Travel 0.1%
	45,000	Vail Resorts (a)		2,421
		Ski Resort Operator & Developer
				2,421
Consumer Goods & Services: Total				283,156
Industrial Goods & Services 12.9%
		> Machinery 8.3%
	697,500	Ametek		32,671
		Aerospace/Industrial Instruments
	650,300	ESCO Technologies (a)		25,973
		Automatic Electric Meter Readers
	673,600	Pentair		23,448
		Pumps & Water Treatment
	373,600	Nordson		21,654
		Dispensing Systems for Adhesives & Coatings
	394,800	Donaldson		18,311
		Industrial Air Filtration
	71,800	Toro		3,909
		Turf Maintenance Equipment
	50,000	Kaydon		2,727
		Specialized Friction & Motion Control Products
	21,823	MOOG (a)		999
		Motion Control Products for Aerospace, Defense & Industrial Markets
				129,692
		> Other Industrial Services 1.6%
	415,000	American Commercial Lines (a)		6,740
		Operator/Builder of Inland Barges
	179,000	G&K Services		6,716
		Uniform Rental
	396,000	American Reprographics (a)		6,526
		Document Management & Logistics
	350,000	TrueBlue (a)		5,068
		Temporary Manual Labor
				25,050
		> Outsourcing Services 0.9%
	350,000	Quanta Services (a)		9,184
		Electrical & Telecom Construction Services
	175,000	Administaff		4,949
		Professional Employer Organization
				14,133
		> Construction 0.6%
	50,000	Texas Industries		3,505
		Aggregates, Cement & Concrete
	100,000	Simpson Manufacturing		2,659
		Wall Joint Maker

Number of Shares			Value (000)
	23,589	Vulcan Materials	$	1,865
		Aggregates, Concrete & Asphalt
	140,000	M/I Homes		1,470
		Home Builder
				9,499
		> Waste Management 0.5%
	280,875	Waste Connections (a)		8,679
		Solid Waste Management
				8,679
		> Industrial Materials & Specialty Chemicals 0.5%
	155,000	Drew Industries (a)		4,247
		RV & Manufactured Home Components
	90,000	Albany International		3,339
		Paper Machine Clothing & Advanced Textiles
				7,586
		> Industrial Distribution 0.5%
	225,000	Interline Brands (a)		4,930
		Industrial Distribution
	70,000	Watsco		2,573
		HVAC Distribution
				7,503
Industrial Goods & Services: Total				202,142
Health Care 11.6%
		> Biotechnology & Drug Delivery 5.1%
	700,000	BioMarin (a)		24,780
		Biotech Focused on Orphan Diseases
	885,000	PDL BioPharma (a)		15,505
		Proprietary Monoclonal Antibodies
	421,400	Seattle Genetics (a)		4,804
		Antibody-based Therapies for Cancer
	100,000	Myriad Genetics (a)		4,642
		Drugs/Diagnostics Hybrid
	545,000	Array Biopharma (a)		4,589
		Drugs for Cancer & Inflammatory Diseases
	1,135,000	Decode Genetics (a)		4,177
		Drugs for Heart Attack, Asthma & Vascular Disease
	580,000	Nektar Therapeutics (a)		3,892
		Drug Delivery Technologies
	320,000	Medarex (a)		3,334
		Humanized Antibodies
	401,000	Arena Pharmaceuticals (a)		3,140
		Novel Drug Targeting Technology
	40,000	Alexion Pharmaceuticals (a)		3,001
		Biotech Focused on Orphan Diseases
	2,824,700	Medicure (a)		2,825
	738,060	Medicure - Warrants (a)(c)		295
		Cardiovascular Biotech Company
	400,000	Neurogen (a)		1,380
		Development-stage Biotech Focused on Neurology
	220,000	Pharmacopeia (a)		1,049
		Biotech Company with Broad Early-stage Pipeline

See accompanying notes to financial statements.

46

Number of Shares			Value (000)
		> Biotechnology & Drug Delivery—continued
	500,000	IsoRay (a)	$	990
	100,000	IsoRay - Warrants (a)(c)		5
		Radiology Cancer Company
	273,500	Nuvelo (a)		501
		Development-stage Biotech Focused on Cardiovascular/Cancer
	57,499	La Jolla Pharmaceutical (a)		225
		Lupus Treatment
	37,500	Locus Pharmaceuticals, Series A-1, Pfd. (a)(c)		98
	19,329	Locus Pharmaceuticals, Series B-1, Pfd. (a)(c)		50
		High Throughput Rational Drug Design
	18,181	Metabolex, Series F (a)(c)		30
		Diabetes Drug Development
				79,312
		> Health Care Services 2.0%
	660,000	PSS World Medical (a)		12,916
		Medical Supplies
	291,800	Lincare Holdings (a)		10,260
		Home Health Care Services
	137,000	Charles River Laboratories (a)		9,014
		Pharmaceutical Research
				32,190
		> Pharmaceuticals 1.6%
	145,000	Cephalon (a)		10,405
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	180,000	Medicis Pharmaceutical		4,674
		Specialty Pharmaceuticals for Dermatology
	1,040,000	QLT (a)		4,597
		Specialty Pharmaceuticals for Ophthalmology & Dermatology
	300,000	Collagenex Pharmaceuticals (a)		2,865
		Specialty Pharmaceuticals for Dermatology
	505,000	Barrier Therapeutics (a)		1,990
		Specialty Pharmaceuticals for Dermatology
				24,531
		> Medical Supplies 1.5%
	158,300	Techne (a)		10,456
		Cytokines, Antibodies & other Reagents for Life Science
	270,700	ICU Medical (a)		9,748
		Intravenous Therapy Products
	200,000	QIAGEN (Netherlands) (a)		4,210
		Life Science Company; DNA/RNA Purification
				24,414
		> Medical Equipment & Devices 1.4%
	111,360	Orthofix International (a)		6,456
		Bone Fixation & Stimulation Devices
	115,405	Edwards Lifesciences (a)		5,307
		Heart Valves
	85,000	Illumina (a)		5,037
		Leading Tools & Service Provider for Genetic Analysis
	50,000	Vital Signs		2,556
		Anesthesia, Respiratory & Sleep Products

Number of Shares			Value (000)
	94,171	Advanced Medical Optics (a)	$	2,310
		Medical Devices for Eye Care
				21,666
Health Care: Total				182,113
Energy & Minerals 11.2%
		> Oil Services 6.3%
	803,400	FMC Technologies (a)		45,553
		Oil & Gas Wellhead Manufacturer
	330,000	Atwood Oceanics (a)		33,079
		Offshore Drilling Contractor
	115,375	Exterran Holdings (a)		9,438
		Natural Gas Compressor Rental & Fabrication
	241,000	Tetra Technologies (a)		3,752
		U.S. Based Service Company with Life of Field Approach
	129,000	Tesco (a)		3,698
		Developing New Well Drilling Technologies
	59,800	CARBO Ceramics		2,225
		Natural Gas Well Stimulants
				97,745
		> Oil & Gas Producers 4.1%
	525,000	Quicksilver Resources (a)		31,285
		Natural Gas & Coal Seam Gas Producer
	311,193	Carrizo Oil & Gas (a)		17,038
		Explores for Natural Gas & Crude Oil
	138,400	Southwestern Energy (a)		7,711
		Oil & Gas Producer
	111,200	Equitable Resources		5,925
		Natural Gas Producer & Utility
	450,000	Vaalco Energy (a)		2,092
		Oil & Gas Producer
				64,051
		> Other Resources 0.7%
	218,000	Layne Christensen (a)		10,728
		Oil & Gas Production/Engineering & Construction/Contract Drilling
				10,728
		> Oil Refining, Marketing & Distribution 0.1%
	50,250	Oneok		2,250
		Natural Gas Distribution, Pipeline Processing & Trading
				2,250
Energy & Minerals: Total				174,774
Finance 9.4%
		> Banks 3.4%
	212,756	Chittenden		7,578
		New England Bank
	205,000	MB Financial		6,320
		Chicago Bank
	289,698	Lakeland Financial		6,055
		Indiana Bank
	220,000	Old Second Bancorp		5,894
		Illinois Bank

See accompanying notes to financial statements.

47

Columbia Acorn USA

Statement of Investments, continued

Number of Shares			Value (000)
		> Banks—continued
	213,600	Associated Banc-Corp	$	5,786
		Midwest Bank
	280,777	Glacier Bancorp		5,262
		Mountain States Bank
	408,000	Pacific Continental		5,084
		Niche Pacific N.W. Bank
	215,000	First Busey		4,270
		Illinois Bank
	149,800	TCF Financial		2,686
		Great Lakes Bank
	130,000	Greene County Bancshares		2,496
		Tennessee Bank
	108,300	Valley National Bancorp		2,064
		New Jersey/New York Bank
	15,000	West Bancorporation		196
		Des Moines Commercial Bank
				53,691
		> Insurance 2.7%
	714,500	HCC Insurance Holdings		20,492
		Specialty Insurance
	14,000	Markel (a)		6,875
		Specialty Insurance
	105,000	Philadelphia Consolidated Holding (a)		4,132
		Specialty Insurance
	75,000	Endurance Specialty Holdings		3,130
		Commercial Lines Insurance/Reinsurance
	87,000	Delphi Financial Group		3,069
		Group Employee Benefit Products & Services
	166,593	Eastern Insurance Holdings		2,742
		Workers Comp. & Specialty Insurance
	200,000	Meadowbrook Insurance Group (a)		1,882
		Specialty Insurance Products & Services
				42,322
		> Finance Companies 2.5%
	1,136,500	AmeriCredit (a)		14,536
		Auto Lending
	482,900	World Acceptance (a)		13,029
		Personal Loans
	130,000	McGrath Rentcorp		3,347
		Temporary Space & IT Rentals
	175,000	H & E Equipment Services (a)		3,304
		Heavy Equipment Leasing
	140,000	Aaron Rents		2,694
		Rent-to-own
	100,000	Marlin Business Services (a)		1,206
		Small Equipment Leasing
	66,953	Electro Rent		994
		Test & Measurement Rentals
				39,110
		> Brokerage & Money Management 0.4%
	150,000	SEI Investments		4,825
		Mutual Fund Administration & Investment Management
	110,923	Thomas Weisel Partners Group (a)		1,523
		Boutique Bay Area Investment Bank
				6,348

Number of Shares or Principal Amount (000)			Value (000)
		> Savings & Loans 0.4%
	258,000	People's United	$	4,592
		Connecticut Savings & Loan
	46,200	Anchor Bancorp Wisconsin		1,087
		Wisconsin Thrift
				5,679
Finance: Total				147,150
Other Industries 2.0%
		> Real Estate 1.3%
	560,000	DiamondRock Hospitality		8,389
		Hotel Owner
	100,000	Digital Realty Trust		3,837
		Technology-focused Office Buildings
	77,500	Gaylord Entertainment (a)		3,136
		Convention Hotels
	90,000	American Campus Communities		2,416
		Student Housing
	150,000	Kite Realty Group		2,291
		Community Shopping Centers
				20,069
		> Transportation 0.7%
	524,720	Heartland Express		7,441
		Regional Trucker
	177,353	Rush Enterprises (a)		3,224
		Truck Distribution
				10,665
Other Industries: Total				30,734
Total Equities: 99.1% (Cost: $1,208,449)				1,550,418
Short-Term Obligations 2.2%
$	8,100	Toyota Motor Credit 4.18% Due 1/02/08		8,099
	25,801	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by a U.S. Government Agency Obligation, maturing 2/06/17, market value $26,322 (repurchase proceeds $25,805)		25,801
		(Amortized Cost: $33,900)		33,900
Total Investments: 101.3% (Cost: $1,242,349)(d)				1,584,318
Cash and Other Assets Less Liabilities: (1.3)%				(20,376	)
Total Net Assets: 100%			$	1,563,942

See accompanying notes to financial statements.

48

> Notes to Statement of Investments (dollar values in thousands)

(a)  Non-income producing security.

(b)  An affiliate may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in this affiliated company during the twelve months ended December 31, 2007, are as follows:

Affiliates	Balance of Shares Held 12/31/06		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/07		Value		Dividend
RCM Technologies		786,000		-		-		786,000	$	4,622	$	-

  The aggregate cost and value of these companies at December 31, 2007, was $5,636 and $4,622 respectively. Investments in affiliate companies represented 0.30% of total net assets at December 31, 2007.

(c)  Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued in good faith by the board of trustees. At December 31, 2007, these securities amounted to $478 which represented 0.03% of total net assets.

  Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Locus Pharmaceuticals, Series A-1 Pfd.	9/5/01		37,500	$	1,500	$	98
Locus Pharmaceuticals, Series B-1 Pfd.	2/8/07		19,329		56		50
Metabolex, Series F	5/11/00		18,181		2,000		30
IsoRay - Warrants	3/21/07		100,000		-		5
Medicure - Warrants	12/22/06		738,060		-		295
				$	3,556	$	478

(d)  At December 31, 2007, for federal income tax purposes cost of investments was $1,242,593 and net unrealized appreciation was $341,725 consisting of gross unrealized appreciation of $494,581 and gross unrealized depreciation of $152,856.

See accompanying notes to financial statements.

49

Columbia Acorn International Select

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	09/30/07		12/31/07
Additions
Europe
> Netherlands
Fugro		143,500		170,000
QIAGEN		135,000		170,000
> United Kingdom
Informa Group		370,000		470,000
Intertek Testing		135,000		310,000
> Ireland
United Drug		959,600		1,100,000
> Sweden
Hexagon		360,000		390,000
Securitas Systems		857,000		1,030,000
> France
SES Global		343,000		370,000
Asia
> Japan
Hoya		188,000		215,000
Ibiden		70,000		75,000
> China
China Shipping Development		1,250,000		1,795,000
Jiangsu Expressway		2,500,000		5,500,000
Lenovo Group		7,300,000		8,600,000
VisionChina Media		0		53,000
Other Countries
> United States
Diamond Offshore		55,000		60,000
> South Africa
Impala Platinum Holdings		203,000		215,000
Uranium One		0		400,000
> Canada
Petro Rubiales Energy-Warrants		0		343,200
> Australia
Sino Gold		303,259		1,256,000
Latin America
> Brazil
BM&F		0		101,000
Bovespa		0		140,400

	Number of Shares
	09/30/07		12/31/07
Sales
Europe
> Netherlands
USG People		29,000		0
> Switzerland
Geberit		20,500		0
Nobel Biocare Holding		23,000		10,000
> Ireland
CRH		132,037		75,000
> Germany
Deutsche Boerse		19,500		15,000
Asia
> Japan
Nintendo		20,000		16,500
Park24		350,000		0
Ushio		76,500		0
> Hong Kong
Hong Kong Exchanges and Clearing		299,000		215,000
Other Countries
> Canada
Potash Corp. of Saskatchewan		90,000		59,400

See accompanying notes to financial statements.

50

Columbia Acorn International Select

Statement of Investments, December 31, 2007

Number of Shares			Value (000)
				Equities: 91.5%
Europe 47.3%
		> Netherlands 9.6%
	170,000	Fugro	$	13,031
		Oilfield Services
	170,000	QIAGEN (a)		3,651
		Life Science Company; DNA/RNA Purification
	142,000	Aalberts Industries		2,799
		Flow Control & Heat Treatment
	87,000	SBM Offshore		2,729
		Builds & Leases Offshore Vessels to Process & Store Crude Oil
	76,700	OPG Groep		2,119
		Health Care Supplies & Pharmacies
	23,100	Boskalis Westminster		1,403
		Dredging & Maritime Contractor
	74,000	Wavin		979
		Largest European Plastic Pipe Systems Company
				26,711
		> Switzerland 7.0%
	75,000	Kuehne & Nagel		7,150
		Freight Forwarding/Logistics
	45,000	Synthes		5,562
		Products for Orthopedic Surgery
	10,000	Nobel Biocare Holding		2,645
		Dental Implants & Ceramic Crowns
	7,500	Swatch Group		2,249
		Watch & Electronics Manufacturer
	26,000	Schindler		1,662
		Elevator Manufacturer & Service Provider
				19,268
		> United Kingdom 6.4%
	650,000	Smith & Nephew		7,473
		Medical Equipment & Supplies
	310,000	Intertek Testing		6,078
		Testing, Inspection, Certification Services
	470,000	Informa Group		4,299
		Global Publisher & Event Organizer
				17,850
		> Ireland 4.9%
	1,100,000	United Drug		6,343
		Irish Pharmaceutical Wholesaler & Outsourcer
	205,000	IAWS Group		4,538
		Baked Goods
	75,000	CRH		2,604
		Global Building Materials
				13,485
		> Sweden 4.2%
	390,000	Hexagon		8,042
		Measurement Equipment & Polymers
	1,030,000	Securitas Systems		3,634
		Commercial Security Installation & Service
				11,676

Number of Shares			Value (000)
		> France 3.5%
	370,000	SES Global	$	9,702
		Satellite Broadcasting Services
				9,702
		> Germany 3.3%
	40,000	Wincor Nixdorf		3,769
		Retail POS Systems & ATM Machines
	15,000	Deutsche Boerse		2,961
		Trading, Clearing, Settlement Services for Financial Markets
	1,250	Porsche		2,519
		Specialty Automobile Manufacturer
				9,249
		> Austria 2.6%
	200,000	Zumtobel		7,179
		Lighting Systems
				7,179
		> Greece 2.5%
	350,000	Intralot		6,897
		Lottery & Gaming Systems & Services
				6,897
		> Spain 2.0%
	55,000	Red Electrica de Espana		3,457
		Spanish Power Grid
	110,000	Prisa		2,045
		Leading Spanish-speaking Publisher
				5,502
		> Denmark 1.3%
	31,000	Novozymes		3,499
		Industrial Enzymes
				3,499
Europe: Total				131,018
Asia 24.4%
		> Japan 13.2%
	16,500	Nintendo		10,018
		Entertainment Software & Hardware
	8,500	Jupiter Telecommunications (a)		7,191
		Largest Cable Service Provider in Japan
	215,000	Hoya		6,862
		Opto-electrical Components & Eyeglass Lenses
	75,000	Ibiden		5,180
		Electronic Parts & Ceramics
	600,000	Kansai Paint		4,352
		Paint Producer in Japan, India, China & Southeast Asia
	1,800	Kenedix		2,896
		Real Estate Investment Management
				36,499
		> China 6.7%
	8,600,000	Lenovo Group		7,604
		Third Largest PC Vendor Globally
	5,500,000	Jiangsu Expressway		5,935
		Chinese Toll Road Operator

See accompanying notes to financial statements.

51

Columbia Acorn International Select

Statement of Investments, continued

Number of Shares			Value (000)
		> China—continued
	1,795,000	China Shipping Development	$	4,681
		China's Dominant Shipper for Oil & Coal
	53,000	VisionChina Media (a)		451
		Advertising on Digital Screens in China's Mass Transit System
				18,671
		> Hong Kong 2.2%
	215,000	Hong Kong Exchanges and Clearing		6,036
		Hong Kong Equity & Derivatives Market Operator
				6,036
		> Singapore 1.2%
	364,000	Singapore Exchange		3,327
		Singapore Equity & Derivatives Market Operator
				3,327
		> South Korea 1.1%
	105,200	Sung Kwang Bend		3,019
		A Large Customized Industrial Pipe Fitting Manufacturer
				3,019
Asia: Total				67,552
Other Countries 18.3%
		> South Africa 5.7%
	215,000	Impala Platinum Holdings		7,417
		Platinum Group Metals Mining & Refining
	198,000	Naspers		4,661
		Media & Education in Africa & other Emerging Markets
	400,000	Uranium One (a)		3,578
		Uranium Mines in South Africa, Kazakhstan, Australia & the U.S.
				15,656
		> Canada 5.2%
	59,400	Potash Corp. of Saskatchewan		8,551
		World's Largest Producer of Potash
	2,000,000	Petro Rubiales Energy (Canada) (a)(b)		2,914
	828,400	Petro Rubiales Energy - Warrants (Canada) (a)(b)		457
		Oil Production & Exploration in Colombia
	137,000	RONA (a)		2,367
		Leading Canadian Do-it-yourself Retailer
				14,289
		> United States 4.7%
	60,000	Diamond Offshore		8,520
		Contract Driller
	45,500	Atwood Oceanics (a)		4,561
		Offshore Drilling Contractor
				13,081

Number of Shares or Principal Amount (000)			Value (000)
		> Australia 2.7%
	1,256,000	Sino Gold (a)	$	7,601
		Gold Mining in The People's Republic of China
				7,601
Other Countries: Total				50,627
Latin America 1.5%
		> Brazil 1.5%
	140,400	Bovespa (a)		2,705
		Brazil Equity & Derivative Exchange
	101,000	BM&F (a)		1,419
		Brazilian Derivatives Exchange
				4,124
Latin America: Total				4,124
Total Equities: 91.5% (Cost: $198,448)				253,321
Short-Term Obligation 4.4%
$	12,288	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by a U.S. Government Agency Obligation, maturing 7/18/16, market value $12,537 (repurchase proceeds $12,290)		12,288
		(Cost: $12,288)		12,288
Total Investments: 95.9% (Cost: $210,736)(c)(d)				265,609
Cash and Other Assets Less Liabilities: (e) 4.1%				11,408
Total Net Assets: 100%			$	277,017

See accompanying notes to financial statements.

52

> Notes to Statement of Investments (dollar values in thousands)

(a)  Non-income producing security.

(b)  Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued in good faith by the board of trustees. At December 31, 2007, these securities amounted to $2,867 which represented 1.04% of total net assets.

  Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Petro Rubiales Energy	7/12/07		1,656,800	$	1,109	$	2,410
Petro Rubiales Energy - Warrants	7/12/07		828,400		236		457
				$	1,345	$	2,867

(c)  At December 31, 2007, for federal income tax purposes cost of investments was $210,962 and net unrealized appreciation was $54,647 consisting of gross unrealized appreciation of $65,182 and gross unrealized depreciation of $10,535.

(d)  On December 31, 2007, the Fund's total investments were denominated in currencies as follows:

Currency	Value		% of Net Assets
Euro	$	78,724		28.4	%
Japanese Yen		36,499		13.2
US Dollar		34,371		12.4
Hong Kong Dollar		24,256		8.8
Swiss Franc		19,269		7.0
British Pound		17,850		6.4
Other currencies less than 5% of total net assets		54,640		19.7
	$	265,609		95.9	%

(e)  Included in Cash and Other Assets Less Liabilities is $12,808 of Japanese Yen.

See accompanying notes to financial statements.

53

Columbia Acorn International Select

Portfolio Diversification

At December 31, 2007, the Fund's portfolio investments as a percent of net assets were diversified as follows:

	Value (000)		Percent
> Information
Financial Processors	$	12,324		4.4	%
Computer Hardware & Related Equipment		11,373		4.1
Consumer Software		10,018		3.6
Satellite Broadcasting & Services		9,702		3.5
CATV		7,191		2.6
Semiconductors & Related Equipment		6,862		2.5
Publishing		6,344		2.3
TV Broadcasting		4,661		1.7
Advertising		451		0.2
		68,926		24.9
> Energy & Minerals
Oil Services		30,243		11.0
Mining		27,148		9.8
Oil & Gas Producers		3,371		1.2
		60,762		22.0
> Industrial Goods & Services
Conglomerates		16,021		5.8
Other Industrial Services		14,890		5.4
Industrial Materials & Specialty Chemicals		8,830		3.2
Electrical Components		7,179		2.6
Outsourcing Services		3,634		1.3
Machinery		3,019		1.1
Construction		2,604		0.9
		56,177		20.3

	Value (000)		Percent
> Health Care
Medical Equipment & Devices	$	15,680		5.7	%
Pharmaceuticals		6,343		2.3
Medical Supplies		3,651		1.3
Health Care Services		2,119		0.7
		27,793		10.0
> Consumer Goods & Services
Casinos & Gaming		6,897		2.5
Other Durable Goods		4,768		1.7
Food & Beverage		4,538		1.6
Retail		2,367		0.9
		18,570		6.7
> Other Industries
Transportation		10,616		3.8
Regulated Utilities		3,457		1.3
Real Estate		2,896		1.0
		16,969		6.1
> Finance
Brokerage & Money Management		4,124		1.5
		4,124		1.5
Total Equities:		253,321		91.5
Short-Term Obligations:		12,288		4.4
Total Investments:		265,609		95.9
Cash and Other Assets Less Liabilities:		11,408		4.1
Net Assets:	$	277,017		100.0	%

See accompanying notes to financial statements.

54

Columbia Acorn Select

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	09/30/07		12/31/07
Additions
Consumer Goods & Services
Chico's FAS		3,100,000		3,500,000
Knoll		0		1,370,000
Information
Cardtronics		0		2,308,000
Globalstar		6,000,000		6,866,316
Novell		6,900,000		7,250,000
Sanmina-SCI		27,500,000		36,700,000
Tellabs		15,000,000		17,000,000
VisionChina Media (China)		0		1,675,000
Energy & Minerals
Tetra Technologies		5,000,000		5,550,000
Uranium One (South Africa)		17,215,800		18,000,000
Finance
Bovespa (Brazil)		0		661,600
Conseco		8,300,000		9,700,000
Janus Capital Group		4,100,000		4,150,000
Industrial Goods & Services
American Commercial Lines		2,450,000		3,000,000
American Reprographics		0		1,000,000

	Number of Shares
	09/30/07		12/31/07
Sales
Information
Canadian Solar		2,700,000		2,400,000
Discovery Holding		3,000,000		2,500,000
Liberty Global, Series A		600,000		0
Liberty Global, Series C		3,000,000		0
Energy & Minerals
Potash Corp. of Saskatchewan (Canada)		1,440,000		1,370,000

See accompanying notes to financial statements.

55

Columbia Acorn Select

Statement of Investments, December 31, 2007

Number of Shares			Value (000)
				Equities: 94.9%
Consumer Goods & Services 25.6%
		> Retail 11.2%
	1,650,000	Abercrombie & Fitch	$	131,950
		Teen Apparel Retailer
	3,550,000	Safeway		121,446
		Supermarkets
	850,000	Costco Wholesale		59,296
		Warehouse Superstores
	3,500,000	Chico's FAS (a)		31,605
		Women's Specialty Retailer
				344,297
		> Travel 4.7%
	3,550,000	Expedia (a)		112,251
		Online Travel Services Company
	2,000,000	Hertz (a)		31,780
		Largest U.S. Rental Car Operator
				144,031
		> Other Consumer Services 4.4%
	1,300,000	ITT Educational Services (a)		110,851
		Post-secondary Degree Services
	1,500,000	Universal Technical Institute (a)(b)		25,500
		Vocational Training
				136,351
		> Leisure Products 2.2%
	800,000	Harley-Davidson		37,368
		Motorcycles & Related Merchandise
	750,000	International Speedway		30,885
		Largest Motorsports Racetrack Owner & Operator
				68,253
		> Furniture & Textiles 1.6%
	850,000	Herman Miller		27,532
		Office Furniture
	1,370,000	Knoll		22,509
		Office Furniture
				50,041
		> Apparel 1.5%
	1,550,000	Coach (a)		47,399
		Designer & Retailer of Branded Leather Accessories
				47,399
Consumer Goods & Services: Total				790,372
Information 23.1%
		> Mobile Communications 4.9%
	2,300,000	American Tower (a)		97,980
		Communications Towers in USA & Mexico
	6,866,316	Globalstar (a)(b)		54,931
		Satellite Mobile Voice & Data Carrier
				152,911
		> Business Software 3.8%
	2,350,000	Avid Technology (a)(b)		66,599
		Digital Nonlinear Editing Software & Systems

Number of Shares			Value (000)
	7,250,000	Novell (a)	$	49,807
		Directory, Operating System & Identity Management Software
				116,406
		> Telecommunications Equipment 3.6%
	17,000,000	Tellabs (a)		111,180
		Telecommunications Equipment
				111,180
		> Internet Related 3.0%
	9,600,000	SkillSoft (a)(b)		91,776
		Web-based Learning Solutions (E-Learning)
				91,776
		> Semiconductors & Related Equipment 2.2%
	2,400,000	Canadian Solar (a)(b)		67,560
		Solar Cell & Module Manufacturer
				67,560
		> Contract Manufacturing 2.2%
	36,700,000	Sanmina-SCI (a)(b)		66,794
		Electronic Manufacturing Services
				66,794
		> CATV 2.0%
	2,500,000	Discovery Holding (a)		62,850
		CATV Programming
				62,850
		> Financial Processors 0.7%
	2,308,000	Cardtronics (a)(b)		23,334
		Operates the World's Largest Network of ATMs
				23,334
		> Advertising 0.5%
	1,675,000	VisionChina Media (China) (a)		14,238
		Advertising on Digital screens in China's Mass Transit System
				14,238
		> Computer Services 0.2%
	1,367,000	AnswerThink (a)		6,616
		IT Integration & Best Practice Research
				6,616
Information: Total				713,665
Energy & Minerals 20.8%
		> Mining 11.6%
	1,370,000	Potash Corp. of Saskatchewan (Canada)		197,225
		World's Largest Producer of Potash
	18,000,000	Uranium One (South Africa) (a)		161,042
		Uranium Mines in South Africa, Kazakhstan, Australia & the U.S.
				358,267
		> Oil Services 6.5%
	5,550,000	Tetra Technologies (a)(b)		86,413
		U.S. Based Service Company with Life of Field Approach
	1,200,000	FMC Technologies (a)		68,040
		Oil & Gas Wellhead Manufacturer

See accompanying notes to financial statements.

56

Number of Shares			Value (000)
		> Oil Services—continued
	300,000	Atwood Oceanics (a)	$	30,072
		Offshore Drilling Contractor
	125,000	Diamond Offshore		17,750
		Contract Driller
				202,275
		> Oil & Gas Producers 2.7%
	50,000,000	Petro Rubiales Energy (Canada) (a)(b)(c)		72,726
	17,212,500	Petro Rubiales Energy-Warrants (Canada) (a)(b)(c)		9,496
		Oil Production & Exploration in Colombia
				82,222
Energy & Minerals: Total				642,764
Finance 13.6%
		> Insurance 7.1%
	9,700,000	Conseco (a)(b)		121,832
		Life, Long-term Care & Medical Supplement Insurance
	112,000	Markel (a)		55,003
		Specialty Insurance
	2,400,000	Montpelier Re		40,824
		Commercial Lines Insurance/Reinsurance
				217,659
		> Brokerage & Money Management 6.5%
	4,150,000	Janus Capital Group		136,327
		Manages Mutual Funds
	1,600,000	SEI Investments		51,472
		Mutual Fund Administration & Investment Management
	661,600	Bovespa (Brazil) (a)		12,749
		Brazil Equity & Derivative Exchange
				200,548
Finance: Total				418,207
Industrial Goods & Services 9.5%
		> Other Industrial Services 4.2%
	1,425,000	Expeditors International of Washington		63,669
		International Freight Forwarder
	3,000,000	American Commercial Lines (a)(b)		48,720
		Operator/Builder of Inland Barges
	1,000,000	American Reprographics (a)		16,480
		Document Management & Logistics
				128,869
		> Outsourcing Services 2.4%
	2,800,000	Quanta Services (a)		73,472
		Electrical & Telecom Construction Services
				73,472
		> Waste Management 1.6%
	1,500,000	Waste Management		49,005
		U.S. Garbage Collection & Disposal
				49,005

Number of Shares or Principal Amount (000)			Value (000)
		> Steel 1.3%
	2,350,000	Worthington Industries	$	42,018
		Steel Processing & Manufactured Metal Products
				42,018
Industrial Goods & Services: Total				293,364
Health Care 1.2%
		> Health Care Services 1.2%
	1,000,000	Lincare Holdings (a)		35,160
		Home Health Care Services
				35,160
Health Care: Total				35,160
Other Industries 1.1%
		> Transportation 1.1%
	1,250,000	JB Hunt Transport Services		34,437
		Truck & Intermodal Carrier
				34,437
Other Industries: Total				34,437
Total Equities: 94.9% (Cost: $2,194,475)				2,927,969
Short-Term Obligations 5.0%
$	15,600	General Electric Capital 4.18% Due 1/08/08		15,587
	15,500	Parker-Hannifin (d) 4.45% Due 1/25/08		15,454
	15,400	Chevron Funding 4.11% Due 1/04/08		15,395
	15,400	Toyota Motor Credit 4.15% Due 1/07/08		15,389
	15,300	Emerson Electric (d) 4.18% Due 1/16/08		15,274
	15,300	United Parcel Services (d) 3.98% Due 1/17/08		15,273
	14,900	Hershey Foods (d) 4.22% Due 1/02/08		14,898
	14,900	IBM Corporation (d) 4.24% Due 1/03/08		14,897
	31,023	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by a U.S. Government Agency Obligation, maturing 7/18/16, market value $31,649 (repurchase proceeds $31,028)		31,023
		(Amortized Cost: $153,190)		153,190
Total Investments: 99.9% (Cost: $2,347,665)(e)				3,081,159
Cash and Other Assets Less Liabilities: 0.1%				4,000
Total Net Assets: 100%			$	3,085,159

See accompanying notes to financial statements.

57

Columbia Acorn Select

Statement of Investments, continued

> Notes to Statement of Investments (dollar values in thousands)

(a)  Non-income producing security.

(b)  An affiliate may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in affiliated companies during the twelve months ended December 31, 2007, are as follows:

Affiliates	Balance of Shares Held 12/31/06		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/07		Value		Dividend
American Commercial Lines		-		3,000,000		-		3,000,000	$	48,720	$	-
Avid Technology		2,200,000		150,000		-		2,350,000		66,599		-
Canadian Solar		550,000		2,150,000		300,000		2,400,000		67,560		-
Cardtronics		-		2,308,000		-		2,308,000		23,334		-
Conseco		2,000,000		7,700,000		-		9,700,000		121,832		-
Globalstar		1,600,000		5,266,316		-		6,866,316		54,931		-
Petro Rubiales Energy		-		50,000,000		-		50,000,000		72,726		-
Petro Rubiales Energy-Warrants		-		17,212,500		-		17,212,500		9,496		-
Sanmina-SCI		10,330,000		26,370,000		-		36,700,000		66,794		-
SkillSoft		9,600,000		-		-		9,600,000		91,776		-
Tetra Technologies		-		5,550,000		-		5,550,000		86,413		-
Universal Technical Institute		1,350,000		150,000		-		1,500,000		25,500		-
UrAsia Energy (merged into Uranium One)*		30,050,000		2,000,000		32,050,000		-		-		-
TOTAL OF AFFILIATED TRANSACTIONS		57,680,000		121,856,816		32,350,000		147,186,816	$	735,681	$	-

*  At December 31, 2007, the Fund owned less than five percent of the company's outstanding voting shares.

  The aggregate cost and value of these companies at December 31, 2007, was $820,725 and $735,681 respectively. Investments in affiliate companies represented 23.8% of total net assets at December 31, 2007.

(c)  Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued in good faith by the board of trustees. At December 31, 2007, these securities amounted to $82,075 which represented 2.66% of net assets.

  Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Petro Rubiales Energy	7/12/07		49,900,000	$	37,653	$	72,579
Petro Rubiales Energy-Warrants	7/12/07		17,212,500		4,910		9,496
				$	42,563	$	82,075

(d)  Security exempt from registration under Section 4(2) of the Securities Act of 1933. These securities may only be resold in exempt transactions to qualified buyers. Private resales of these securities to qualified institutional buyers are also exempt from registration pursuant to Rule 144A under the Securities Act of 1933. At December 31, 2007, these securities had an aggregate value of $75,796, which represented 2.5% of net assets.

(e)  At December 31, 2007, for federal income tax purposes cost of investments was $2,357,720 and net unrealized appreciation was $723,439 consisting of gross unrealized appreciation of $1,021,303 and gross unrealized depreciation of $297,864.

See accompanying notes to financial statements.

58

Columbia Thermostat Fund

Statement of Investments, December 31, 2007

Number of Shares or Principal Amount (000)			Value (000)
		> Bond Funds: 64.9%
	6,788,152	Columbia Intermediate Bond Fund, Class Z	$	59,600
	3,274,079	Columbia U.S. Treasury Index Fund, Class Z		35,720
	2,948,910	Columbia Conservative High Yield Fund, Class Z		23,798
Total Bond Funds (Cost: $119,036)				119,118
		> Stock Funds: 34.6%
	1,112,902	Columbia Large Cap Enhanced Core Fund, Class Z		15,859
	865,633	Columbia Dividend Income Fund, Class Z		12,690
	218,964	Columbia Acorn International, Class Z		9,547
	321,754	Columbia Acorn Fund, Class Z		9,527
	408,455	Columbia Marsico Growth Fund, Class Z		9,517
	224,606	Columbia Acorn Select, Class Z		6,381
Total Stock Funds (Cost: $57,066)				63,521
Short-Term Obligation: 0.9%
$	1,608	Repurchase Agreement with Fixed Income Clearing Corp., dated 12/31/07, due 1/02/08 at 3.00%, collateralized by a U.S. Government Agency Obligation, maturing 8/20/12, market value $1,641 (repurchase proceeds $1,608)		1,608
		(Cost: $1,608)		1,608
Total Investments: 100.4% (Cost: $177,710)(a)				184,247
Cash and Other Assets Less Liabilities: (0.4)%				(719	)
Total Net Assets: 100%			$	183,528

> Notes to Statement of Investments (dollar values in thousands)

(a)  At December 31, 2007, for federal income tax purposes cost of investments was $178,495 and net unrealized appreciation was $5,752, consisting of gross unrealized appreciation of $7,296 and gross unrealized depreciation of $1,544.

See accompanying notes to financial statements.

59

Columbia Acorn Family of Funds

Statements of Assets and Liabilities

December 31, 2007	Columbia Acorn Fund			Columbia Acorn International			Columbia Columbia Acorn USA			Acorn International Select			Columbia Acorn Select			Columbia Thermostat Fund
(in thousands)
Assets:
Unaffiliated investments, at cost	$	9,458,367		$	3,887,622		$	1,236,713		$	210,736		$	1,526,940		$	1,608
Affiliated investments, at cost (See Note 4)		3,677,369			89,822			5,636			—			820,725			176,102
Unaffiliated investments, at value	$	14,902,114		$	5,753,160		$	1,579,696		$	265,609		$	2,345,478		$	1,608
Affiliated investments, at value (See Note 4)		5,035,542			77,254			4,622			—			735,681			182,639
Cash		—	*		167			123			—	*		748			—	*
Foreign currency (cost: Columbia Acorn Fund $2,383; Columbia Acorn International $8,509; Columbia Acorn International Select $12,598; Columbia Acorn Select $1)		2,407			8,515			—			12,808			1			—
Receivable for:
Investments sold		27,446			9,535			18,538			15			504			—
Fund shares sold		36,632			16,576			809			829			15,277			450
Dividends and interest		9,053			6,478			479			207			502			—	*
Foreign tax reclaims		185			340			—			24			—			—
Trustees' Deferred Compensation Investments		2,966			808			222			—			219			—
Total Assets		20,016,345			5,872,833			1,604,489			279,492			3,098,410			184,697
Liabilities:
Expense reimbursement due to Investment Adviser		—			—			—			—			—			3
Payable for:
Investments purchased		41,848			9,053			3,894			1,793			4,168			672
Fund shares redeemed		31,272			58,644			34,629			251			5,398			275
Management fee		10,955			3,781			1,185			218			2,084			15
Administration fee		648			188			52			9			100			6
12b-1 Service & Distribution fees		2,875			326			134			28			538			77
Reports to shareholders		814			234			92			22			199			40
Deferred Trustees' fees		2,966			808			222			30			219			24
Transfer agent fees		3,183			386			293			23			476			38
Trustees' fees		—	*		—	*		—	*		1			—	*		1
Audit fee		50			51			28			29			28			17
Custody fees		233			470			5			21			18			—
Chief compliance officer expenses		24			7			2			—	*		4			—	*
Deferred foreign capital gains tax payable		—			521			—			—			—			—
Other liabilities		131			36			11			50			19			1
Total Liabilities		94,999			74,505			40,547			2,475			13,251			1,169
Net Assets	$	19,921,346		$	5,798,328		$	1,563,942		$	277,017		$	3,085,159		$	183,528
Composition of Net Assets:
Paid in capital	$	12,765,066		$	3,854,515		$	1,170,442		$	216,960		$	2,287,904		$	176,414
Undistributed (overdistributed) net investment income (Accumulated net investment loss)		(7,414	)		9,909			(222	)		163			(10,038	)		167
Accumulated net realized gain		361,714			81,387			51,753			4,807			73,799			410
Net unrealized appreciation on:
Investments		6,801,920			1,852,970			341,969			54,873			733,494			6,537
Foreign capital gains tax		—			(521	)		—			—			—			—
Foreign currency translations		60			68			—			214			—	*		—
Net Assets	$	19,921,346		$	5,798,328		$	1,563,942		$	277,017		$	3,085,159		$	183,528
Net asset value per share – Class A (a)	$	28.87		$	43.42		$	27.23		$	31.74		$	27.89		$	12.31
(Net assets/shares)		($4,300,920/148,979)			($622,901/14,345)			($245,085/9,000)			($48,538/1,529)			($1,117,941/40,081)			($53,246/4,325)
Maximum offering price per share – Class A (b)	$	30.63		$	46.07		$	28.89		$	33.68		$	29.59		$	13.06
(Net asset value per share/front- end sales charge)		($28.87/0.9425)			($43.42/0.9425)			($27.23/0.9425)			($31.74/0.9425)			($27.89/0.9425)			($12.31/0.9425)
Net asset value and offering price per share – Class B (a)	$	27.39		$	42.46		$	25.87		$	30.50		$	26.57		$	12.38
(Net assets/shares)		($1,270,292/46,378)			($103,631/2,441)			($53,820/2,080)			($11,941/392)			($199,182/7,496)			($67,709/5,471)
Net asset value and offering price per share – Class C (a)	$	27.25		$	42.32		$	25.77		$	30.42		$	26.46		$	12.37
(Net assets/shares)		($1,312,243/48,162)			($153,416/3,625)			($50,743/1,969)			($13,023/428)			($197,100/7,449)			($26,908/2,175)
Net asset value and offering price per share – Class Z (c)	$	29.61		$	43.60		$	27.97		$	32.02		$	28.41		$	12.26
(Net assets/shares)		($13,037,891/440,350)			($4,918,380/112,805)			($1,214,294/43,419)			($203,515/6,356)			($1,570,936/55,302)			($35,665/2,910)

(a)  Redemption price per share is equal to net asset value less any applicable contingent deferred sales charge and redemption fee.

(b)  On sales of $50,000 or more the offering price is reduced.

(c)  Redemption price per share is equal to net asset value less any applicable redemption fee.

*  Rounds to less than $500.

See accompanying notes to financial statements.

60

Columbia Acorn Family of Funds

Statements of Operations
For the Year Ended December 31, 2007

(in thousands)	Columbia Acorn Fund			Columbia Acorn International			Columbia Columbia Acorn USA			Acorn International Select			Columbia Acorn Select			Columbia Thermostat Fund
Investment Income:
Dividend income	$	145,080		$	87,367		$	12,363		$	3,081		$	9,206		$	—
Dividend income from affiliates (See Note 4)		36,575			2,142			—			—			—			—
Dividends from affiliated investment company shares (See Note 4)		—			—			—			—			—			7,789
Interest income		56,916			17,028			3,194			586			11,149			40
		238,571			106,537			15,557			3,667			20,355			7,829
Foreign taxes withheld		(2,862	)		(6,403	)		—	*		(174	)		(65	)		—
Total Investment Income		235,709			100,134			15,557			3,493			20,290			7,829
Expenses:
Management fee		130,904			40,665			14,381			2,123			23,344			184
Administration fee		7,739			2,012			632			85			1,110			70
12b-1 Service and Distribution fees:
Class A		11,075			1,205			660			90			2,838			134
Class B		10,443			765			461			82			1,648			524
Class C		13,968			1,329			556			99			2,045			266
Transfer agent fees:
Class A		3,186			492			178			38			871			78
Class B		1,990			183			102			24			378			111
Class C		1,311			153			55			15			228			42
Class Z		4,387			1,267			573			75			565			39
Custody fees		1,588			2,881			48			104			128			—
Trustees' fees		822			218			69			24			242			24
Registration & blue sky fees		202			144			81			63			107			56
Reports to shareholders		1,932			620			287			96			529			125
Chief compliance officer expenses (See Note 4)		468			123			45			12			70			12
Other expenses		914			307			113			67			165			45
Total expenses		190,929			52,364			18,241			2,997			34,268			1,710
Less custody fees paid indirectly		(202	)		(2	)		(20	)		—	*		(53	)		—	*
Less reimbursement of expenses by Investment Adviser		—			—			—			—			—			(315	)
Less reimbursement of expenses by Transfer Agent
Class A		(222	)		(16	)		(12	)		(1	)		(54	)		(4	)
Class B		(86	)		(7	)		(4	)		(1	)		(16	)		(5	)
Class C		(63	)		(6	)		(2	)		(1	)		(9	)		(2	)
Class Z		(378	)		(26	)		(49	)		(1	)		(22	)		—	*
Net Expenses		189,978			52,307			18,154			2,993			34,114			1,384
Net Investment Income (Loss)		45,731			47,827			(2,597	)		500			(13,824	)		6,445
Net Realized and Unrealized Gain (Loss) on Portfolio Positions:
Net realized gain (loss) on:
Unaffiliated investments		1,424,022			508,011			134,988			28,059			131,210			—
Affiliated investments (See Note 4)		289,100			6,231			—			—			6,322			6,855
Foreign currency transactions		(1,028	)		(572	)		—			663			(204	)		—
Distributions from affiliated investment company shares		—			—			—			—			—			2,080
Realized loss due to a trading error		(4	)		—			—			—			—			—
Reimbursement of trading loss by Investment Advisor (See Note 8)		4			—			—			—			—			—
Net realized gain		1,712,094			513,670			134,988			28,722			137,328			8,935
Net change in net unrealized appreciation (depreciation) on:
Unaffiliated investments		(363,205	)		241,230			(78,501	)		12,803			228,164			—
Affiliated investments (See Note 4)		27,347			(8,791	)		(86	)		—			(167,579	)		(1,323	)
Foreign currency translations		38			17			—			211			69			—
Foreign capital gains tax		—			(521	)		—			—			—			—
Unrealized loss due to a trading error		—			—			(5	)		—			—			—
Reimbursement of trading loss by Investment Advisor (See Note 8)		—			—			5			—			—			—
Net change in unrealized appreciation (depreciation)		(335,820	)		231,935			(78,587	)		13,014			60,654			(1,323	)
Net realized and unrealized gain		1,376,274			745,605			56,401			41,736			197,982			7,612
Net Increase in Net Assets resulting from Operations	$	1,422,005		$	793,432		$	53,804		$	42,236		$	184,158		$	14,057

*  Rounds to less than $500.

See accompanying notes to financial statements.

61

Columbia Acorn Family of Funds

Statements of Changes in Net Assets

	Columbia Acorn Fund						Columbia Acorn International						Columbia Acorn USA
Increase (Decrease) in Net Assets	Year ended December 31,						Year ended December 31,						Year ended December 31,
(in thousands)	2007			2006			2007			2006			2007			2006
Operations:
Net investment income (loss)	$	45,731		$	35,190		$	47,827		$	31,386		$	(2,597	)	$	(3,110	)
Net realized gain on investments and foreign currency transactions		1,712,094			1,611,966			513,670			392,116			134,988			46,861
Net realized gain on affiliated investment company shares and distributions from affiliated investment company shares		—			—			—			—			—			—
Net change in net unrealized appreciation (depreciation) on investments and foreign currency translations		(335,820	)		712,218			231,935			645,701			(78,587	)		64,360
Net change in net unrealized appreciation (depreciation) on affiliated investment company shares		—			—			—			—			—			—
Net Increase from Operations		1,422,005			2,359,374			793,432			1,069,203			53,804			108,111
Distribution to Shareholders From:
Net investment income – Class A		(3,413	)		(5,394	)		(1,116	)		(2,223	)		—			—
Net realized gain – Class A		(325,538	)		(313,513	)		(43,244	)		(26,545	)		(15,400	)		(5,181	)
Net investment income – Class B		—			—			—	*		(141	)		—			—
Net realized gain – Class B		(102,379	)		(114,707	)		(7,707	)		(8,646	)		(3,468	)		(1,487	)
Net investment income – Class C		—			—			(2	)		(63	)		—			—
Net realized gain – Class C		(105,787	)		(109,093	)		(11,335	)		(8,998	)		(3,257	)		(1,223	)
Net investment income – Class Z		(48,153	)		(48,532	)		(35,860	)		(44,617	)		—			—
Net realized gain – Class Z		(960,719	)		(916,129	)		(359,596	)		(342,510	)		(72,632	)		(25,202	)
Total Distribution to Shareholders		(1,545,989	)		(1,507,368	)		(458,860	)		(433,743	)		(94,757	)		(33,093	)
Share Transactions:
Subscriptions – Class A		1,059,415			1,078,213			364,862			176,101			90,692			113,090
Distributions reinvested – Class A		298,039			288,002			40,913			25,843			13,230			4,383
Redemptions – Class A		(1,097,778	)		(822,590	)		(115,689	)		(63,857	)		(96,876	)		(51,382	)
Net Increase (Decrease) – Class A		259,676			543,625			290,086			138,087			7,046			66,091
Subscriptions – Class B		14,689			25,556			17,916			17,920			496			1,247
Distributions reinvested – Class B		93,667			104,566			7,027			8,016			3,174			1,351
Redemptions – Class B		(235,941	)		(212,371	)		(22,565	)		(20,296	)		(13,338	)		(14,036	)
Net Increase (Decrease) – Class B		(127,585	)		(82,249	)		2,378			5,640			(9,668	)		(11,438	)
Subscriptions – Class C		110,348			166,508			60,335			50,734			3,126			17,895
Distributions reinvested – Class C		83,502			86,726			8,403			6,707			2,798			1,038
Redemptions – Class C		(210,477	)		(178,699	)		(21,288	)		(16,582	)		(8,675	)		(8,640	)
Net Increase (Decrease) – Class C		(16,627	)		74,535			47,450			40,859			(2,751	)		10,293
Subscriptions – Class Z		1,935,968			1,754,910			996,581			707,961			236,636			371,430
Distributions reinvested – Class Z		863,071			824,254			279,036			279,893			65,865			22,838
Redemptions – Class Z		(1,814,299	)		(1,413,279	)		(495,473	)		(357,229	)		(272,461	)		(175,498	)
Net Increase – Class Z		984,740			1,165,885			780,144			630,625			30,040			218,770
Net Increase (Decrease) from Share Transactions		1,100,204			1,701,796			1,120,058			815,211			24,667			283,716
Redemption Fees		—			—			303			147			—			—
Total Increase (Decrease) in Net Assets		976,220			2,553,802			1,454,933			1,450,818			(16,286	)		358,734
Net Assets:
Beginning of period		18,945,126			16,391,324			4,343,395			2,892,577			1,580,228			1,221,494
End of period	$	19,921,346		$	18,945,126		$	5,798,328		$	4,343,395		$	1,563,942		$	1,580,228
Undistributed (Overdistributed) Net Investment Income or (Accumulated Net Investment Loss)	$	(7,414	)	$	(27,265	)	$	9,909		$	(20,256	)	$	(222	)	$	(174	)

*  Rounds to less than $500.

See accompanying notes to financial statements.

62

	Columbia Acorn International Select						Columbia Acorn Select						Columbia Thermostat Fund
Increase (Decrease) in Net Assets	Year ended December 31,						Year ended December 31,						Year ended December 31,
(in thousands)	2007			2006			2007			2006			2007			2006
Operations:
Net investment income (loss)	$	500		$	361		$	(13,824	)	$	(11,032	)	$	6,445		$	6,358
Net realized gain on investments and foreign currency transactions		28,722			18,110			137,328			71,803			—			—
Net realized gain on affiliated investment company shares and distributions from affiliated investment company shares		—			—			—			—			8,935			11,669
Net change in net unrealized appreciation (depreciation) on investments and foreign currency translations		13,014			20,770			60,654			287,875			—			—
Net change in net unrealized appreciation (depreciation) on affiliated investment company shares		—			—			—			—			(1,323	)		836
Net Increase from Operations		42,236			39,241			184,158			348,646			14,057			18,863
Distribution to Shareholders From:
Net investment income – Class A		(150	)		(2	)		—			(788	)		(2,012	)		(2,086	)
Net realized gain – Class A		(2,498	)		—			(25,546	)		(20,503	)		(3,166	)		(3,300	)
Net investment income – Class B		—			—			—			—			(2,100	)		(2,114	)
Net realized gain – Class B		(655	)		—			(4,903	)		(4,991	)		(4,129	)		(3,980	)
Net investment income – Class C		—			—	*		—			—			(764	)		(753	)
Net realized gain – Class C		(682	)		—			(4,795	)		(3,972	)		(1,608	)		(1,496	)
Net investment income – Class Z		(1,618	)		(196	)		—			(1,614	)		(1,519	)		(1,223	)
Net realized gain – Class Z		(10,710	)		—			(33,588	)		(19,241	)		(2,094	)		(1,585	)
Total Distribution to Shareholders		(16,313	)		(198	)		(68,832	)		(51,109	)		(17,392	)		(16,537	)
Share Transactions:
Subscriptions – Class A		26,720			10,850			353,434			210,532			10,451			6,298
Distributions reinvested – Class A		2,409			2			23,371			19,667			4,734			4,887
Redemptions – Class A		(7,228	)		(3,070	)		(257,380	)		(158,467	)		(19,044	)		(25,185	)
Net Increase (Decrease) – Class A		21,901			7,782			119,425			71,732			(3,859	)		(14,000	)
Subscriptions – Class B		2,760			2,223			3,529			4,782			4,269			3,578
Distributions reinvested – Class B		583			—			4,372			4,452			5,698			5,496
Redemptions – Class B		(2,545	)		(1,437	)		(36,416	)		(31,688	)		(13,592	)		(16,105	)
Net Increase (Decrease) – Class B		798			786			(28,515	)		(22,454	)		(3,625	)		(7,031	)
Subscriptions – Class C		5,815			2,333			44,306			20,817			4,372			4,114
Distributions reinvested – Class C		579			—	*		3,773			3,230			2,127			1,960
Redemptions – Class C		(1,469	)		(924	)		(32,811	)		(22,947	)		(6,502	)		(7,323	)
Net Increase (Decrease) – Class C		4,925			1,409			15,268			1,100			(3	)		(1,249	)
Subscriptions – Class Z		70,464			34,878			874,944			258,516			6,608			5,698
Distributions reinvested – Class Z		5,636			99			25,110			14,293			3,354			2,633
Redemptions – Class Z		(21,559	)		(10,107	)		(274,110	)		(170,328	)		(4,141	)		(3,204	)
Net Increase – Class Z		54,541			24,870			625,944			102,481			5,821			5,127
Net Increase (Decrease) from Share Transactions		82,165			34,847			732,122			152,859			(1,666	)		(17,153	)
Redemption Fees		31			9			—			—			—			—
Total Increase (Decrease) in Net Assets		108,119			73,899			847,448			450,396			(5,001	)		(14,827	)
Net Assets:
Beginning of period		168,898			94,999			2,237,711			1,787,315			188,529			203,356
End of period	$	277,017		$	168,898		$	3,085,159		$	2,237,711		$	183,528		$	188,529
Undistributed (Overdistributed) Net Investment Income or (Accumulated Net Investment Loss)	$	163		$	676		$	(10,038	)	$	(9,971	)	$	167		$	249

63

Columbia Acorn Family of Funds

Statements of Changes in Net Assets, continued

	Columbia Acorn Fund						Columbia Acorn International						Columbia Acorn USA
Changes in Shares of Beneficial Interest:	Year ended December 31,						Year ended December 31,						Year ended December 31,
(in thousands)	2007			2006			2007			2006			2007			2006
Subscriptions – Class A		34,304			37,015			8,200			4,588			3,109			4,113
Shares issued in reinvestment and capital gains – Class A		10,082			9,911			931			673			475			156
Less shares redeemed – Class A		(35,563	)		(28,264	)		(2,608	)		(1,723	)		(3,347	)		(1,877	)
Net Increase (Decrease) – Class A		8,823			18,662			6,523			3,538			237			2,392
Subscriptions – Class B		501			909			410			482			18			47
Shares issued in reinvestment and capital gains – Class B		3,332			3,757			164			212			119			50
Less shares redeemed – Class B		(7,999	)		(7,576	)		(523	)		(553	)		(478	)		(533	)
Net Increase (Decrease) – Class B		(4,166	)		(2,910	)		51			141			(341	)		(436	)
Subscriptions – Class C		3,792			5,931			1,389			1,356			113			678
Shares issued in reinvestment and capital gains – Class C		2,987			3,123			196			178			105			39
Less shares redeemed – Class C		(7,188	)		(6,396	)		(487	)		(455	)		(312	)		(328	)
Net Increase (Decrease) – Class C		(409	)		2,658			1,098			1,079			(94	)		389
Subscriptions – Class Z		61,171			58,774			22,406			18,601			7,861			13,228
Shares issued in reinvestment and capital gains – Class Z		28,499			27,709			6,321			7,251			2,304			796
Less shares redeemed – Class Z		(57,473	)		(47,499	)		(11,085	)		(9,331	)		(9,118	)		(6,302	)
Net Increase – Class Z		32,197			38,984			17,642			16,521			1,047			7,722
Net Increase (Decrease) in Shares of Beneficial Interest		36,445			57,394			25,314			21,279			849			10,067

*  Rounds to less than 500 shares.

See accompanying notes to financial statements.

64

	Columbia Acorn International Select						Columbia Acorn Select						Columbia Thermostat Fund
Changes in Shares of Beneficial Interest:	Year ended December 31,						Year ended December 31,						Year ended December 31,
(in thousands)	2007			2006			2007			2006			2007			2006
Subscriptions – Class A		867			446			12,257			8,645			805			492
Shares issued in reinvestment and capital gains – Class A		75			—	*		810			777			380			390
Less shares redeemed – Class A		(230	)		(131	)		(8,919	)		(6,607	)		(1,469	)		(1,960	)
Net Increase (Decrease) – Class A		712			315			4,148			2,815			(284	)		(1,078	)
Subscriptions – Class B		93			97			129			207			328			279
Shares issued in reinvestment and capital gains – Class B		19			—	*		159			183			456			437
Less shares redeemed – Class B		(86	)		(64	)		(1,320	)		(1,373	)		(1,046	)		(1,253	)
Net Increase (Decrease) – Class B		26			33			(1,032	)		(983	)		(262	)		(537	)
Subscriptions – Class C		194			100			1,601			898			338			322
Shares issued in reinvestment and capital gains – Class C		19			—	*		138			133			170			156
Less shares redeemed – Class C		(49	)		(42	)		(1,197	)		(1,002	)		(502	)		(572	)
Net Increase (Decrease) – Class C		164			58			542			29			6			(94	)
Subscriptions – Class Z		2,248			1,448			29,644			10,565			511			442
Shares issued in reinvestment and capital gains – Class Z		176			5			858			559			271			210
Less shares redeemed – Class Z		(696	)		(427	)		(9,406	)		(7,111	)		(320	)		(248	)
Net Increase – Class Z		1,728			1,026			21,096			4,013			462			404
Net Increase (Decrease) in Shares of Beneficial Interest		2,630			1,432			24,754			5,874			(78	)		(1,305	)

65

Columbia Acorn Family of Funds

Financial Highlights

Columbia Acorn Fund

Class A Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	29.02		$	27.57		$	25.93		$	22.20		$	15.34
Income from Investment Operations
Net investment income (loss) (a)		0.05	(b)		0.05			0.07			(0.05	)		(0.07	)
Net realized and unrealized gain		2.13			3.82			3.20			4.69			6.95
Total from Investment Operations		2.18			3.87			3.27			4.64			6.88
Less Distributions Declared to Shareholders
From net investment income		(0.03	)		(0.04	)		(0.07	)		—			—
From net realized gains		(2.30	)		(2.38	)		(1.56	)		(0.91	)		(0.02	)
Total Distributions Declared to Shareholders		(2.33	)		(2.42	)		(1.63	)		(0.91	)		(0.02	)
Net Asset Value, End of Period	$	28.87		$	29.02		$	27.57		$	25.93		$	22.20
Total Return (c)		7.39	%(d)(e)		14.13	%(d)		12.76	%(d)		21.05	%(d)		44.85	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.02	%		1.02	%		1.03	%		1.20	%		1.33	%
Net investment income (loss) (f)		0.17	%		0.17	%		0.28	%		(0.21	)%		(0.36	)%
Waiver/reimbursement		0.01	%		0.02	%		0.02	%		0.02	%		—
Portfolio turnover rate		20	%		22	%		16	%		20	%		10	%
Net assets at end of period (000's)	$	4,300,920		$	4,067,868		$	3,349,461		$	2,669,936		$	1,982,260

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.03 per share.

(c)  Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Total return includes a voluntary reimbursement by the Investment Adviser for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by less than 0.01% and $0.01, respectively.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

Class B Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	27.78		$	26.61		$	25.19		$	21.75		$	15.13
Income from Investment Operations
Net investment loss (a)		(0.11	)(b)		(0.13	)		(0.11	)		(0.22	)		(0.18	)
Net realized and unrealized gain		2.02			3.68			3.09			4.57			6.82
Total from Investment Operations		1.91			3.55			2.98			4.35			6.64
Less Distributions Declared to Shareholders
From net realized gains		(2.30	)		(2.38	)		(1.56	)		(0.91	)		(0.02	)
Total Distributions Declared to Shareholders		(2.30	)		(2.38	)		(1.56	)		(0.91	)		(0.02	)
Net Asset Value, End of Period	$	27.39		$	27.78		$	26.61		$	25.19		$	21.75
Total Return (c)		6.76	%(d)(e)		13.43	%(d)		11.98	%(d)		20.15	%(d)		43.89	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.59	%		1.66	%		1.72	%		1.95	%		1.98	%
Net investment loss (f)		(0.39	)%		(0.48	)%		(0.42	)%		(0.96	)%		(1.01	)%
Waiver/reimbursement		0.01	%		0.02	%		0.02	%		0.02	%		—
Portfolio turnover rate		20	%		22	%		16	%		20	%		10	%
Net assets at end of period (000's)	$	1,270,292		$	1,404,165		$	1,422,580		$	1,399,135		$	1,221,931

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.03 per share.

(c)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Total return includes a voluntary reimbursement by the Investment Adviser for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by less than 0.01% and $0.01, respectively.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

Class C Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	27.70		$	26.58		$	25.18		$	21.75		$	15.12
Income from Investment Operations
Net investment loss (a)		(0.18	)(b)		(0.17	)		(0.13	)		(0.22	)		(0.18	)
Net realized and unrealized gain		2.03			3.67			3.09			4.56			6.83
Total from Investment Operations		1.85			3.50			2.96			4.34			6.65
Less Distributions Declared to Shareholders
From net realized gains		(2.30	)		(2.38	)		(1.56	)		(0.91	)		(0.02	)
Total Distributions Declared to Shareholders		(2.30	)		(2.38	)		(1.56	)		(0.91	)		(0.02	)
Net Asset Value, End of Period	$	27.25		$	27.70		$	26.58		$	25.18		$	21.75
Total Return (c)		6.56	%(d)(e)		13.25	%(d)		11.90	%(d)		20.11	%(d)		43.99	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.79	%		1.80	%		1.82	%		1.95	%		1.98	%
Net investment loss (f)		(0.60	)%		(0.61	)%		(0.51	)%		(0.96	)%		(1.01	)%
Waiver/reimbursement		0.00	%(g)		0.02	%		0.02	%		0.02	%		—
Portfolio turnover rate		20	%		22	%		16	%		20	%		10	%
Net assets at end of period (000's)	$	1,312,243		$	1,345,520		$	1,220,339		$	1,083,006		$	900,016

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.03 per share.

(c)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Total return includes a voluntary reimbursement by the Investment Adviser for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by less than 0.01% and $0.01, respectively.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g)  Rounds to less than 0.01%.

See accompanying notes to financial statements.

66

Columbia Acorn International

Class A Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	40.07		$	33.20		$	28.75		$	22.45		$	15.32
Income from Investment Operations
Net investment income (a)		0.27			0.23			0.22			0.14			0.10
Net realized and unrealized gain		6.52			10.87			5.84			6.31			7.08
Total from Investment Operations		6.79			11.10			6.06			6.45			7.18
Less Distributions Declared to Shareholders
From net investment income		(0.08	)		(0.32	)		(0.53	)		(0.15	)		(0.05	)
From net realized gains		(3.36	)		(3.91	)		(1.08	)		—			—
Total Distributions Declared to Shareholders		(3.44	)		(4.23	)		(1.61	)		(0.15	)		(0.05	)
Redemption Fees
Redemption fees added to paid in capital		0.00	(a)(b)		0.00	(a)(b)		0.00	(a)(b)		0.00	(a)(b)		—
Net Asset Value, End of Period	$	43.42		$	40.07		$	33.20		$	28.75		$	22.45
Total Return (c)		16.90	%(d)		34.16	%(d)		21.42	%(d)		28.91	%(d)		46.94	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (e)		1.23	%		1.24	%		1.30	%		1.48	%		1.59	%
Net investment income (e)		0.60	%		0.61	%		0.72	%		0.61	%		0.57	%
Waiver/reimbursement		0.00	%(f)		0.01	%		0.02	%		0.02	%		—
Portfolio turnover rate		28	%		31	%		27	%		40	%		40	%
Net assets at end of period (000's)	$	622,901		$	313,401		$	142,204		$	70,582		$	52,872

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Rounds to less than $0.01 per share.

(c)  Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(f)  Rounds to less than 0.01%.

Class B Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	39.39		$	32.71		$	28.18		$	22.07		$	15.11
Income from Investment Operations
Net investment income (loss) (a)		0.04			(0.00	)(b)		0.02			(0.04	)		(0.02	)
Net realized and unrealized gain		6.39			10.66			5.73			6.19			6.98
Total from Investment Operations		6.43			10.66			5.75			6.15			6.96
Less Distributions Declared to Shareholders
From net investment income		(0.00	)(b)		(0.07	)		(0.14	)		(0.04	)		—
From net realized gains		(3.36	)		(3.91	)		(1.08	)		—			—
Total Distributions Declared to Shareholders		(3.36	)		(3.98	)		(1.22	)		(0.04	)		—
Redemption Fees
Redemption fees added to paid in capital		0.00	(a)(b)		0.00	(a)(b)		0.00	(a)(b)		0.00	(a)(b)		—
Net Asset Value, End of Period	$	42.46		$	39.39		$	32.71		$	28.18		$	22.07
Total Return (c)		16.25	%(d)		33.26	%(d)		20.57	%(d)		27.91	%(d)		46.06	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (e)		1.81	%		1.89	%		2.01	%		2.27	%		2.24	%
Net investment income (loss) (e)		0.08	%		(0.01	)%		0.08	%		(0.18	)%		(0.10	)%
Waiver/reimbursement		0.01	%		0.02	%		0.02	%		0.02	%		—
Portfolio turnover rate		28	%		31	%		27	%		40	%		40	%
Net assets at end of period (000's)	$	103,631		$	94,165		$	73,572		$	54,752		$	39,800

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Rounds to less than $0.01 per share.

(c)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

Class C Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	39.35		$	32.68		$	28.19		$	22.06		$	15.11
Income from Investment Operations
Net investment loss (a)		(0.06	)		(0.05	)		(0.00	)(b)		(0.03	)		(0.01	)
Net realized and unrealized gain		6.39			10.66			5.71			6.20			6.96
Total from Investment Operations		6.33			10.61			5.71			6.17			6.95
Less Distributions Declared to Shareholders
From net investment income		(0.00	)(b)		(0.03	)		(0.14	)		(0.04	)		—
From net realized gains		(3.36	)		(3.91	)		(1.08	)		—			—
Total Distributions Declared to Shareholders		(3.36	)		(3.94	)		(1.22	)		(0.04	)		—
Redemption Fees
Redemption fees added to paid in capital		0.00	(a)(b)		0.00	(a)(b)		0.00	(a)(b)		0.00	(a)(b)		—
Net Asset Value, End of Period	$	42.32		$	39.35		$	32.68		$	28.19		$	22.06
Total Return (c)		16.01	%(d)		33.14	%(d)		20.45	%(d)		28.01	%(d)		46.00	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (e)		1.99	%		2.01	%		2.09	%		2.24	%		2.24	%
Net investment loss (e)		(0.14	)%		(0.14	)%		(0.01	)%		(0.15	)%		(0.06	)%
Waiver/reimbursement		0.00	%(f)		0.01	%		0.02	%		0.02	%		—
Portfolio turnover rate		28	%		31	%		27	%		40	%		40	%
Net assets at end of period (000's)	$	153,416		$	99,425		$	47,325		$	30,547		$	22,990

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Rounds to less than $0.01 per share.

(c)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(f)  Rounds to less than 0.01%.

See accompanying notes to financial statements.

67

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn USA

Class A Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	28.02		$	26.52		$	24.77		$	20.74		$	14.18
Income from Investment Operations
Net investment loss (a)		(0.09	)(b)		(0.10	)		(0.01	)		(0.24	)		(0.22	)
Net realized and unrealized gain		1.01			2.21			3.13			4.41			6.78
Total from Investment Operations		0.92			2.11			3.12			4.17			6.56
Less Distributions Declared to Shareholders
From net realized gains		(1.71	)		(0.61	)		(1.37	)		(0.14	)		—
Net Asset Value, End of Period	$	27.23		$	28.02		$	26.52		$	24.77		$	20.74
Total Return (c)		3.18	%(d)(e)		7.95	%(d)		12.68	%(d)		20.12	%(d)		46.26	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.25	%		1.26	%		1.31	%		1.51	%		1.65	%
Net investment income (loss) (f)		(0.29	)%		(0.35	)%		(0.02	)%		(1.08	)%		(1.26	)%
Waiver/reimbursement		0.00	%(g)		0.01	%		0.01	%		0.02	%		—
Portfolio turnover rate		21	%		13	%		13	%		18	%		7	%
Net assets at end of period (000's)	$	245,085		$	245,552		$	168,922		$	112,509		$	89,650

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.09 per share.

(c)  Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Total return includes a voluntary reimbursement by the Investment Adviser for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by less than 0.01% and $0.01, respectively.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g)  Rounds to less than 0.01%.

Class B Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	26.87		$	25.61		$	24.14		$	20.36		$	14.01
Income from Investment Operations
Net investment loss (a)		(0.25	)(b)		(0.27	)		(0.18	)		(0.39	)		(0.32	)
Net realized and unrealized gain		0.96			2.14			3.02			4.31			6.67
Total from Investment Operations		0.71			1.87			2.84			3.92			6.35
Less Distributions Declared to Shareholders
From net realized gains		(1.71	)		(0.61	)		(1.37	)		(0.14	)		—
Net Asset Value, End of Period	$	25.87		$	26.87		$	25.61		$	24.14		$	20.36
Total Return (c)		2.53	%(d)(e)		7.29	%(d)		11.84	%(d)		19.26	%(d)		45.32	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.85	%		1.93	%		2.00	%		2.23	%		2.30	%
Net investment loss (f)		(0.87	)%		(1.01	)%		(0.72	)%		(1.80	)%		(1.91	)%
Waiver/reimbursement		0.01	%		0.02	%		0.01	%		0.02	%		—
Portfolio turnover rate		21	%		13	%		13	%		18	%		7	%
Net assets at end of period (000's)	$	53,820		$	65,040		$	73,168		$	72,643		$	66,175

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.09 per share.

(c)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Total return includes a voluntary reimbursement by the Investment Adviser for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by less than 0.01% and $0.01, respectively.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

Class C Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	26.81		$	25.59		$	24.14		$	20.36		$	14.01
Income from Investment Operations
Net investment loss (a)		(0.30	)(b)		(0.30	)		(0.20	)		(0.39	)		(0.32	)
Net realized and unrealized gain		0.97			2.13			3.02			4.31			6.67
Total from Investment Operations		0.67			1.83			2.82			3.92			6.35
Less Distributions Declared to Shareholders
From net realized gains		(1.71	)		(0.61	)		(1.37	)		(0.14	)		—
Net Asset Value, End of Period	$	25.77		$	26.81		$	25.59		$	24.14		$	20.36
Total Return (c)		2.39	%(d)(e)		7.14	%(d)		11.76	%(d)		19.26	%(d)		45.32	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		2.03	%		2.05	%		2.10	%		2.23	%		2.30	%
Net investment loss (f)		(1.07	)%		(1.14	)%		(0.81	)%		(1.80	)%		(1.91	)%
Waiver/reimbursement		0.00	%(g)		0.01	%		0.01	%		0.02	%		—
Portfolio turnover rate		21	%		13	%		13	%		18	%		7	%
Net assets at end of period (000's)	$	50,743		$	55,306		$	42,844		$	39,643		$	35,662

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.09 per share.

(c)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Total return includes a voluntary reimbursement by the Investment Adviser for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by less than 0.01% and $0.01, respectively.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g)  Rounds to less than 0.01%.

See accompanying notes to financial statements.

68

Columbia Acorn International Select

Class A Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	27.68		$	20.36		$	17.85		$	14.45		$	10.24
Income from Investment Operations
Net investment income (loss) (a)		0.04	(b)		0.03			0.06			(0.00	)(c)		0.03
Net realized and unrealized gain		5.91			7.29			2.69			3.43			4.18
Total from Investment Operations		5.95			7.32			2.75			3.43			4.21
Less Distributions Declared to Shareholders
From net investment income		(0.12	)		—			(0.24	)		(0.03	)		—
From net realized gains		(1.77	)		—			—			—			—
Total Distributions Declared to Shareholders		(1.89	)		—			(0.24	)		(0.03	)		—
Redemption Fees
Redemption fees added to paid in capital		0.00	(a)(c)		0.00	(a)(c)		0.00	(a)(c)		0.00	(a)(c)		—
Net Asset Value, End of Period	$	31.74		$	27.68		$	20.36		$	17.85		$	14.45
Total Return (d)(e)		21.50	%		35.97	%		15.60	%		23.76	%		41.11	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.49	%		1.58	%		1.70	%		1.75	%		1.80	%
Net investment income (loss) (f)		0.11	%		0.11	%		0.34	%		(0.03	)%		0.24	%
Waiver/reimbursement		0.00	%(g)		0.02	%		0.10	%		0.37	%		0.44	%
Portfolio turnover rate		57	%		47	%		39	%		73	%		69	%
Net assets at end of period (000's)	$	48,538		$	22,599		$	10,219		$	4,357		$	2,557

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.07 per share.

(c)  Rounds to less than $0.01 per share.

(d)  Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deferred sales charge.

(e)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g)  Rounds to less than 0.01%.

Class B Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	26.73		$	19.80		$	17.36		$	14.12		$	10.08
Income from Investment Operations
Net investment loss (a)		(0.13	)(b)		(0.12	)		(0.03	)		(0.10	)		(0.06	)
Net realized and unrealized gain		5.67			7.05			2.61			3.34			4.10
Total from Investment Operations		5.54			6.93			2.58			3.24			4.04
Less Distributions Declared to Shareholders
From net investment income		—			—			(0.14	)		—			—
From net realized gains		(1.77	)		—			—			—			—
Total Distributions Declared to Shareholders		(1.77	)		—			(0.14	)		—			—
Redemption Fees
Redemption fees added to paid in capital		0.00	(a)(c)		0.00	(a)(c)		0.00	(a)(c)		0.00	(a)(c)		—
Net Asset Value, End of Period	$	30.50		$	26.73		$	19.80		$	17.36		$	14.12
Total Return (d)(e)		20.69	%		35.00	%		14.97	%		22.95	%		40.08	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		2.10	%		2.25	%		2.30	%		2.38	%		2.45	%
Net investment loss (f)		(0.45	)%		(0.53	)%		(0.16	)%		(0.66	)%		(0.52	)%
Waiver/reimbursement		0.01	%		0.04	%		0.28	%		0.58	%		0.44	%
Portfolio turnover rate		57	%		47	%		39	%		73	%		69	%
Net assets at end of period (000's)	$	11,941		$	9,787		$	6,594		$	5,097		$	3,162

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.07 per share.

(c)  Rounds to less than $0.01 per share.

(d)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(e)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

Class C Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	26.70		$	19.80		$	17.38		$	14.14		$	10.09
Income from Investment Operations
Net investment loss (a)		(0.20	)(b)		(0.15	)		(0.05	)		(0.11	)		(0.05	)
Net realized and unrealized gain		5.69			7.05			2.60			3.35			4.10
Total from Investment Operations		5.49			6.90			2.55			3.24			4.05
Less Distributions Declared to Shareholders
From net investment income		—			—			(0.13	)		—			—
From net realized gains		(1.77	)		—			—			—			—
Total Distributions Declared to Shareholders		(1.77	)		—			(0.13	)		—			—
Redemption Fees
Redemption fees added to paid in capital		0.00	(a)(c)		0.00	(a)(c)		0.00	(a)(c)		0.00	(a)(c)		—
Net Asset Value, End of Period	$	30.42		$	26.70		$	19.80		$	17.38		$	14.14
Total Return (d)(e)		20.53	%		34.85	%		14.77	%		22.91	%		40.14	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		2.29	%		2.38	%		2.45	%		2.45	%		2.45	%
Net investment loss (f)		(0.68	)%		(0.67	)%		(0.30	)%		(0.73	)%		(0.41	)%
Waiver/reimbursement		0.01	%		0.02	%		0.17	%		0.35	%		0.44	%
Portfolio turnover rate		57	%		47	%		39	%		73	%		69	%
Net assets at end of period (000's)	$	13,023		$	7,060		$	4,083		$	2,543		$	3,691

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.07 per share.

(c)  Rounds to less than $0.01 per share.

(d)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(e)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

See accompanying notes to financial statements.

69

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn Select

Class A Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	26.18		$	22.47		$	20.83		$	18.01		$	13.93
Income from Investment Operations
Net investment loss (a)		(0.15	)		(0.13	)		(0.09	)		(0.16	)		(0.20	)
Net realized and unrealized gain		2.50			4.45			2.32			3.42			4.37
Total from Investment Operations		2.35			4.32			2.23			3.26			4.17
Less Distributions Declared to Shareholders
From net investment income		—			(0.02	)		—			—			—
From net realized gains		(0.64	)		(0.59	)		(0.59	)		(0.44	)		(0.09	)
Total Distributions Declared to Shareholders		(0.64	)		(0.61	)		(0.59	)		(0.44	)		(0.09	)
Net Asset Value, End of Period	$	27.89		$	26.18		$	22.47		$	20.83		$	18.01
Total Return (b)		8.92	%(c)		19.32	%(c)		10.78	%(c)		18.16	%(c)		29.95	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (d)		1.19	%		1.24	%		1.26	%		1.47	%		1.63	%
Net investment loss (d)		(0.52	)%		(0.54	)%		(0.42	)%		(0.86	)%		(1.15	)%
Waiver/reimbursement		0.00	%(e)		0.03	%		0.03	%		0.02	%		—
Portfolio turnover rate		14	%		21	%		19	%		34	%		16	%
Net assets at end of period (000's)	$	1,117,941		$	940,857		$	744,178		$	515,842		$	264,679

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deferred sales charge.

(c)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(d)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(e)  Rounds to less than 0.01%.

Class B Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	25.13		$	21.71		$	20.23		$	17.64		$	13.73
Income from Investment Operations
Net investment loss (a)		(0.31	)		(0.28	)		(0.23	)		(0.31	)		(0.29	)
Net realized and unrealized gain		2.39			4.29			2.24			3.34			4.29
Total from Investment Operations		2.08			4.01			2.01			3.03			4.00
Less Distributions Declared to Shareholders
From net realized gains		(0.64	)		(0.59	)		(0.53	)		(0.44	)		(0.09	)
Net Asset Value, End of Period	$	26.57		$	25.13		$	21.71		$	20.23		$	17.64
Total Return (b)		8.22	%(c)		18.54	%(c)		10.01	%(c)		17.24	%(c)		29.14	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (d)		1.79	%		1.91	%		1.99	%		2.26	%		2.28	%
Net investment loss (d)		(1.12	)%		(1.21	)%		(1.15	)%		(1.65	)%		(1.80	)%
Waiver/reimbursement		0.01	%		0.03	%		0.03	%		0.02	%		—
Portfolio turnover rate		14	%		21	%		19	%		34	%		16	%
Net assets at end of period (000's)	$	199,182		$	214,260		$	206,441		$	185,545		$	118,064

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(c)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(d)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

Class C Shares	Year ended December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	25.07		$	21.69		$	20.23		$	17.64		$	13.73
Income from Investment Operations
Net investment loss (a)		(0.36	)		(0.31	)		(0.25	)		(0.30	)		(0.30	)
Net realized and unrealized gain		2.39			4.28			2.24			3.33			4.30
Total from Investment Operations		2.03			3.97			1.99			3.03			4.00
Less Distributions Declared to Shareholders
From net realized gains		(0.64	)		(0.59	)		(0.53	)		(0.44	)		(0.09	)
Net Asset Value, End of Period	$	26.46		$	25.07		$	21.69		$	20.23		$	17.64
Total Return (b)		8.04	%(c)		18.37	%(c)		9.91	%(c)		17.24	%(c)		29.14	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (d)		1.98	%		2.04	%		2.08	%		2.25	%		2.28	%
Net investment loss (d)		(1.31	)%		(1.34	)%		(1.24	)%		(1.64	)%		(1.80	)%
Waiver/reimbursement		0.00	%(e)		0.03	%		0.03	%		0.02	%		—
Portfolio turnover rate		14	%		21	%		19	%		34	%		16	%
Net assets at end of period (000's)	$	197,100		$	173,152		$	149,160		$	110,435		$	64,212

(a)  Per share data was calculated using the average shares outstanding during the period.

(b)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(c)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(d)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(e)  Rounds to less than 0.01%.

See accompanying notes to financial statements.

70

Columbia Thermostat Fund Class A Shares	Year ended December 31,												Inception March 3, 2003 through December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	12.59		$	12.49		$	13.11		$	12.30		$	10.10
Income from Investment Operations
Net investment income (a)		0.49			0.45			0.39			0.28			0.18
Net realized and unrealized gain		0.53			0.84			0.29			0.81			2.15
Total from Investment Operations		1.02			1.29			0.68			1.09			2.33
Less Distributions Declared to Shareholders
From net investment income		(0.51	)		(0.47	)		(0.39	)		(0.25	)		(0.13	)
From net realized gains		(0.79	)		(0.72	)		(0.91	)		(0.03	)		(0.00	)(b)
Total Distributions Declared to Shareholders		(1.30	)		(1.19	)		(1.30	)		(0.28	)		(0.13	)
Net Asset Value, End of Period	$	12.31		$	12.59		$	12.49		$	13.11		$	12.30
Total Return (c)(d)		8.19	%		10.56	%		5.25	%		8.92	%		23.10	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)(g)		0.50	%		0.50	%		0.50	%		0.50	%		0.57	%(h)
Net investment income (g)		3.75	%		3.53	%		2.97	%		2.23	%		1.86	%(h)
Waiver/reimbursement		0.18	%		0.20	%		0.15	%		0.33	%		0.66	%(h)
Portfolio turnover rate		128	%		66	%		96	%		67	%		61	%
Net assets at end of period (000's)	$	53,246		$	58,013		$	71,034		$	77,092		$	42,271

(a)  Per share data was calculated using the average shares outstanding during the period. Recognition of net investment income by the Fund is affected by the timing of the declaration of dividends by the underlying investment companies in which the Fund invests.

(b)  Rounds to less than $(0.01) per share.

(c)  Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Not annualized.

(f)  Does not include expenses of the investment companies in which the Fund invests.

(g)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h)  Annualized.

Class B Shares	Year ended December 31,												Inception March 3, 2003 through December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	12.62		$	12.51		$	13.14		$	12.32		$	10.10
Income from Investment Operations
Net investment income (a)		0.42			0.38			0.31			0.19			0.10
Net realized and unrealized gain		0.54			0.84			0.28			0.83			2.16
Total from Investment Operations		0.96			1.22			0.59			1.02			2.26
Less Distributions Declared to Shareholders
From net investment income		(0.41	)		(0.39	)		(0.31	)		(0.17	)		(0.04	)
From net realized gains		(0.79	)		(0.72	)		(0.91	)		(0.03	)		(0.00	)(b)
Total Distributions Declared to Shareholders		(1.20	)		(1.11	)		(1.22	)		(0.20	)		(0.04	)
Net Asset Value, End of Period	$	12.38		$	12.62		$	12.51		$	13.14		$	12.32
Total Return (c)(d)		7.71	%		9.91	%		4.56	%		8.27	%		22.38	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)(g)		1.00	%		1.06	%		1.10	%		1.18	%		1.32	%(h)
Net investment income (g)		3.25	%		2.99	%		2.39	%		1.55	%		1.06	%(h)
Waiver/reimbursement		0.19	%		0.23	%		0.19	%		0.29	%		0.66	%(h)
Portfolio turnover rate		128	%		66	%		96	%		67	%		61	%
Net assets at end of period (000's)	$	67,709		$	72,367		$	78,444		$	78,040		$	51,501

(a)  Per share data was calculated using the average shares outstanding during the period. Recognition of net investment income by the Fund is affected by the timing of the declaration of dividends by the underlying investment companies in which the Fund invests.

(b)  Rounds to less than $(0.01) per share.

(c)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Not annualized.

(f)  Does not include expenses of the investment companies in which the Fund invests.

(g)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h)  Annualized.

Class C Shares	Year ended December 31,												Inception March 3, 2003 through December 31,
Selected data for a share outstanding throughout each period	2007			2006			2005			2004			2003
Net Asset Value, Beginning of Period	$	12.62		$	12.51		$	13.13		$	12.32		$	10.10
Income from Investment Operations
Net investment income (a)		0.39			0.36			0.29			0.19			0.11
Net realized and unrealized gain		0.53			0.84			0.29			0.81			2.15
Total from Investment Operations		0.92			1.20			0.58			1.00			2.26
Less Distributions Declared to Shareholders
From net investment income		(0.38	)		(0.37	)		(0.29	)		(0.16	)		(0.04	)
From net realized gains		(0.79	)		(0.72	)		(0.91	)		(0.03	)		(0.00	)(b)
Total Distributions Declared to Shareholders		(1.17	)		(1.09	)		(1.20	)		(0.19	)		(0.04	)
Net Asset Value, End of Period	$	12.37		$	12.62		$	12.51		$	13.13		$	12.32
Total Return (c)(d)		7.36	%		9.72	%		4.49	%		8.13	%		22.38	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)(g)		1.25	%		1.25	%		1.25	%		1.25	%		1.32	%(h)
Net investment income (g)		3.02	%		2.81	%		2.21	%		1.48	%		1.10	%(h)
Waiver/reimbursement		0.19	%		0.23	%		0.19	%		0.26	%		0.66	%(h)
Portfolio turnover rate		128	%		66	%		96	%		67	%		61	%
Net assets at end of period (000's)	$	26,908		$	27,375		$	28,316		$	31,161		$	20,087

(a)  Per share data was calculated using the average shares outstanding during the period. Recognition of net investment income by the Fund is affected by the timing of the declaration of dividends by the underlying investment companies in which the Fund invests.

(b)  Rounds to less than $(0.01) per share.

(c)  Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(d)  Had the Investment Adviser and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e)  Not annualized.

(f)  Does not include expenses of the investment companies in which the Fund invests.

(g)  The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h)  Annualized.

See accompanying notes to financial statements.

71

Columbia Acorn Family of Funds

Notes to Financial Statements

1.  Nature of Operations

Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select and Columbia Thermostat Fund (the "Funds") are each a series of Columbia Acorn Trust (the "Trust"), an open-end management investment company organized as a Massachusetts business trust. The investment objective of each Fund, excluding Columbia Thermostat Fund, is to seek long-term growth of capital. The investment objective of Columbia Thermostat Fund is to provide long-term total return. Columbia Thermostat Fund pursues its investment objective by investing in shares of other mutual funds. As a "fund of funds," under normal circumstances, the Fund allocates at least 95% of its net assets among a selected group of stock and bond mutual funds ("portfolio funds") according to the current level of the Standard & Poor's 500 Stock Index in relation to predetermined ranges set by the Fund's investment adviser. The Fund may invest up to 5% of its net assets plus any cash received that day in cash, repurchase agreements, high quality short-term paper and government securities.

The Funds may issue an unlimited number of shares. The Funds currently offer four classes of shares: Class A, Class B, Class C and Class Z. Effective February 29, 2008, the Funds will no longer offer Class B shares.

Class A shares are sold with a front-end sales charge. Class A shares bought without an initial sales charge in accounts aggregating $1 million up to $50 million at the time of purchase are subject to a 1.00% contingent deferred sales charge ("CDSC") if the shares are sold within 12 months of the date of purchase.

Class B shares are subject to a CDSC if sold within six years of purchase. Class B shares will convert to Class A shares automatically eight years after purchase.

Class C shares are subject to a CDSC on redemptions made within one year after purchase.

Class Z shares are offered continuously at net asset value. There are certain restrictions on the purchase of Class Z shares. Generally, Class Z shares of a Fund may be exchanged for shares of another fund distributed by Columbia Management Distributors, Inc. at no additional charge.

Columbia Acorn International and Columbia Acorn International Select impose a 2% redemption fee on Class A, Class B, Class C and Class Z shares that are redeemed within 60 days or less of purchase. See the discussion of Fund policies regarding the trading of Fund shares as disclosed in the Funds' prospectuses for more information.

The financial highlights for Class Z shares are presented in a separate annual report.

Investment income, realized and unrealized gains and losses, and certain fund-level expenses are allocated pro rata on the basis of the relative net assets of all classes, except each class bears certain expenses unique to that class such as distribution services, transfer agency, and certain other class specific expenses. Differences in class expenses may result in payment of different dividend distributions for each class. All the Funds' share classes have equal rights with respect to voting subject to Fund or class specific matters.

2.  Significant Accounting Policies

>Security valuation

Securities of the Funds are valued at market value or, if a market quotation for a security is not readily available or is deemed not to be reliable because of events or circumstances that have occurred between the market quotation and the time as of which the security is to be valued, the security is valued at a fair value determined in accordance with procedures established by the Board of Trustees. With respect to Columbia Thermostat Fund, investments in portfolio funds are valued at their net asset value as reported by the portfolio funds. A security traded on a securities exchange or in over-the-counter market in which transaction prices are reported is valued at the last sales price at the time of valuation. A security traded principally on NASDAQ is valued at the NASDAQ official closing price. A security for which there is no reported sale on the valuation date is valued at the latest bid quotation. A short-term debt obli gation having a maturity of 60 days or less from the valuation date is valued at amortized cost, which approximates fair value. A security for which a market quotation is not readily available and any other assets are fair valued in accordance with procedures established by the Board of Trustees. The Funds have retained an independent statistical fair value pricing service to assist in the fair valuation process for securities principally traded in a foreign market in order to adjust for possible changes in value that may occur between the close of the foreign exchange and the time as of which the securities are to be valued. If a security is valued at fair value, that value may be different from the last quoted market price for the security.

In September 2006, Statement of Financial Accounting Standards No. 157, Fair Value Measurements ("SFAS 157"), was issued. SFAS 157 is effective for fiscal years beginning after November 15, 2007. SFAS 157 defines fair value, establishes a framework for measuring fair value and expands disclosures

72

about fair value measurements. Management is evaluating the impact the application of SFAS 157 will have on the Funds' financial statement disclosures.

>Repurchase agreements

The Funds may engage in repurchase agreement transactions. The Funds, through their custodians, receive delivery of underlying securities collateralizing repurchase agreements. The custodian determines that the value of the underlying securities is at all times at least equal to the resale price. In the event of default or bankruptcy by the other party to the agreement, realization and/or retention of the collateral may be subject to legal proceedings.

>Foreign currency translations

Values of investments denominated in foreign currencies are converted into U.S. dollars using the spot market rate of exchange at the time of valuation. Purchases and sales of investments and dividend and interest income are translated into U.S. dollars using the spot market rate of exchange prevailing on the respective dates of such transactions. The gain or loss resulting from changes in foreign exchange rates is included with net realized and unrealized gain or loss from investments, as appropriate.

>Security transactions and investment income

Security transactions, investment income and shareholder fund transactions are accounted for on the trade date (date the order to buy or sell is executed) and dividend income and realized gain distributions from other funds are recorded on the ex-dividend date, except that certain dividends from foreign securities are recorded as soon as the information is available to the Funds. Interest income is recorded on the accrual basis and includes amortization of discounts on debt obligations when required for federal income tax purposes. Realized gains and losses from security transactions are recorded on an identified cost basis.

Awards, if any, from class action litigation related to securities owned may be recorded as a reduction of cost of those securities. If the applicable securities are no longer owned, the proceeds are recorded as realized gains.

The Funds estimate the tax character of distributions from real estate investment trusts ("REITs"). Distributions received in excess of income are recorded as a reduction of the cost of the related investments. If the applicable securities are no longer owned, any distributions received in excess of income are recorded as realized gains.

>Restricted Securities

Restricted securities are securities that may only be resold upon registration under federal securities laws or in transactions exempt from registration. In some cases, the issuer of restricted securities has agreed to register such securities for resale at the issuer's expense either upon demand by the Funds or in connection with another registered offering of the securities. Many restricted securities may be resold in the secondary market in transactions exempt from registration. Such restricted securities may be determined to be liquid under criteria established by the Board of Trustees. The Funds will not incur any registration costs upon such resale.

>Use of estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America ("GAAP") requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results may differ from those estimates.

>Fund share valuation

Fund shares are sold and redeemed on a continuing basis at net asset value subject to any applicable sales charge. Net asset value per share is determined daily as of the close of trading on the New York Stock Exchange ("NYSE") on each day the NYSE is open for trading. All income, expenses (other than the Class A, Class B and Class C shares Rule 12b-1 service and distribution fees and the Class A, Class B, Class C and Class Z shares transfer agency fees) and realized and unrealized gains (losses) of a Fund are allocated to each class proportionately on a daily basis for purposes of determining the net asset value of each class. Redemption fees are accounted for as an addition to paid in capital for purposes of determining the net asset value of each class.

>Custody fees/credits

Custody fees are reduced based on each Fund's cash balances maintained with the custodian. The amount is disclosed as a reduction of total expenses on the Statements of Operations.

>Federal income taxes

The Funds have complied with the provisions of the Internal Revenue Code available to regulated investment companies and, in the manner provided therein, distribute all their taxable income, as well as any net realized gain on sales of investments and foreign currency transactions reportable for federal income tax purposes. Columbia Thermostat Fund distributes all of its taxable income, as well as any net realized gain on

73

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

sales of portfolio fund shares and any distributions of net realized gains received by the Fund from its portfolio funds, reportable for federal income tax purposes. Accordingly, the Funds paid no federal income taxes and no federal income tax provision was required.

>Foreign capital gains taxes

Realized gains in certain countries may be subject to foreign taxes at the fund level, at rates ranging from approximately 10% to 15%. The Funds accrue for such foreign taxes on net realized and unrealized gains at the appropriate rate for each jurisdiction.

>Distributions to Shareholders

Distributions to shareholders are recorded on the ex-date.

>Indemnification

In the normal course of business, each Fund enters into contracts that contain a variety of representations and warranties and which provide general indemnities. A Fund's maximum exposure under these arrangements is unknown, as this would involve future claims against the Fund. Also, under the Trust's organizational documents, the Trustees and Officers of the Trust are indemnified against certain liabilities that may arise out of their duties to the Trust. However, based on experience, the Funds expect the risk of loss due to these warranties and indemnities to be minimal.

3.  Federal Tax Information

The timing and character of income and capital gain distributions are determined in accordance with income tax regulations, which may differ from GAAP. Reclassifications are made to the Funds' capital accounts for permanent tax differences to reflect income and gains available for distribution (or available capital loss carryforwards) under income tax regulations.

For the year ended December 31, 2007, permanent book and tax basis differences resulting primarily from differing treatments for distribution reclassifications, tax equalization, foreign currency transactions, passive foreign investment company ("PFIC") adjustments, foreign capital gains tax adjustments and REIT adjustments were identified and reclassified among the components of the Fund's net assets as follows:

	Undistributed/ (Overdistributed) Net Investment Income or (Accumulated Net Investment Loss)			Accumulated Net Realized Gain or (Net Realized Loss)			Paid-In Capital
(in thousands)
Columbia Acorn Fund	$	25,686		$	(106,021	)	$	80,335
Columbia Acorn International		19,316			(37,617	)		18,301
Columbia Acorn USA		2,549			(1,848	)		(701	)
Columbia Acorn International Select		755			(755	)		—
Columbia Acorn Select		13,757			(13,605	)		(152	)
Columbia Thermostat Fund		(132	)		(811	)		943

Net investment income and net realized gains (losses), as disclosed on the Statement of Operations, and net assets were not affected by this reclassification.

The tax character of distributions paid during the years ended December 31, 2007 and December 31, 2006 was as follows:

December 31, 2007	Ordinary Income*		Long-Term Capital Gains
(in thousands)
Columbia Acorn Fund	$	154,770	$	1,391,219
Columbia Acorn International		59,527		399,333
Columbia Acorn USA		—		94,757
Columbia Acorn International Select		1,768		14,545
Columbia Acorn Select		9,164		59,668
Columbia Thermostat Fund		12,086		5,306
December 31, 2006	Ordinary Income*		Long-Term Capital Gains
(in thousands)
Columbia Acorn Fund	$	102,167	$	1,405,201
Columbia Acorn International		47,043		386,698
Columbia Acorn USA		—		33,093
Columbia Acorn International Select		198		—
Columbia Acorn Select		9,493		41,617
Columbia Thermostat Fund		7,031		9,506

*For tax purposes short-term capital gains distributions, if any, are considered ordinary income distributions.

As of December 31, 2007, the components of distributable earnings on a tax basis were as follows:

	Undistributed Ordinary Income		Undistributed Long-term Capital Gains		Net Unrealized Appreciation (Depreciation)*
(in thousands)
Columbia Acorn Fund	$	21,930	$	341,600	$	6,795,790
Columbia Acorn International		20,343		74,297		1,850,478
Columbia Acorn USA		—		53,514		341,725
Columbia Acorn International Select		501		4,740		54,647
Columbia Acorn Select		—		74,034		723,439
Columbia Thermostat Fund		561		824		5,752

* The differences between book-basis and tax-basis net unrealized appreciation/depreciation are primarily due to deferral of losses from wash sales and PFIC adjustments.

Unrealized appreciation and depreciation at December 31, 2007, based on cost of investments for federal income tax purposes, were:

	Unrealized Appreciation		Unrealized Depreciation			Net Unrealized Appreciation
(in thousands)
Columbia Acorn Fund	$	7,838,307	$	(1,042,517	)	$	6,795,790
Columbia Acorn International		2,094,574		(244,096	)		1,850,478
Columbia Acorn USA		494,581		(152,856	)		341,725
Columbia Acorn International Select		65,182		(10,535	)		54,647
Columbia Acorn Select		1,021,303		(297,864	)		723,439
Columbia Thermostat Fund		7,296		(1,544	)		5,752

The following capital loss carryforwards may be available to reduce taxable income arising from future net realized gains
on investments, if any, to the extent permitted by the Internal Revenue Code:

74

Year of Expiration	Columbia Acorn USA			Columbia Acorn International Select
(in thousands)
2009	$	1,012	*	$	—
2010		506	*		6,126
2011		—			2,488
TOTAL	$	1,518		$	8,614

*Of these carryforwards, $2,023 (expiring in 2009 and 2010) remains from Columbia Acorn USA's merger with Stein Roe Small Company Growth Fund on 7/26/2002. Utilization of Stein Roe Small Company Growth Fund's losses could be subject to limitations imposed by the Internal Revenue Code.

The following capital loss carryforwards were utilized during the year ended December 31, 2007:

(in thousands)
Columbia Acorn USA	$	506

The Funds adopted Financial Accounting Standards Board ("FASB") Interpretation No. 48, Accounting for Uncertainty in Income Taxes – an Interpretation of FASB Statement No. 109 ("FIN 48") effective June 29, 2007. FIN 48 requires management to determine whether a tax position of the Fund is more likely than not to be sustained upon examination by the applicable taxing authority, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The tax benefit to be recognized is measured as the largest amount of benefit that is greater than fifty percent likely of being realized upon ultimate settlement. FIN 48 must be applied to all existing tax positions upon initial adoption and the cumulative effect, if any, is to be reporte d as an adjustment to net assets. Management has evaluated the known implications of FIN 48 on its computation of net assets for the Funds. As a result of this evaluation, management believes that FIN 48 does not have any effect on the Fund's financial statements. However, management's conclusions regarding FIN 48 may be subject to review and adjustment at a later date based on factors including, but not limited to, further implementation guidance from the FASB, new tax laws, regulations, and administrative interpretations (including relevant court decisions). Each Fund's federal tax returns for the prior three fiscal years remain subject to examination by the Internal Revenue Service. The Funds are not aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months.

4.  Transactions with Affiliates

Columbia Wanger Asset Management, L.P. ("CWAM") is a wholly owned subsidiary of Columbia Management Group, LLC, which in turn is an indirect, wholly owned subsidiary of Bank of America Corporation ("BOA"). CWAM furnishes continuing investment supervision to the Funds and is responsible for the overall management of the Funds' business affairs.

Effective August 1, 2007, under the Funds' investment advisory agreement, fees are accrued daily based on the Funds' average daily net assets and paid monthly to CWAM at the annual rates shown in the table below for Columbia Acorn International Select:

Columbia Acorn International Select

Average Daily Net Assets	Annual Fee Rate
Up to $500 million		0.94	%
$500 million and over		0.90	%

For all of the other Funds, and also prior to August 1, 2007, for Columbia Acorn International Select, for the period covered by this report as provided under the Funds' investment advisory agreement, fees were accrued daily based on the Funds' average daily net assets and paid monthly to CWAM at the annual rates shown in the table below for each Fund.

Columbia Acorn Fund

Average Daily Net Assets	Annual Fee Rate
Up to $700 million		0.74	%
$700 million to $2 billion		0.69	%
$2 billion to $6 billion		0.64	%
$6 billion and over		0.63	%

Columbia Acorn International

Average Daily Net Assets	Annual Fee Rate
Up to $100 million		1.19	%
$100 million to $500 million		0.94	%
$500 million and over		0.74	%

Columbia Acorn USA

Average Daily Net Assets	Annual Fee Rate
Up to $200 million		0.94	%
$200 million to $500 million		0.89	%
$500 million to $2 billion		0.84	%
$2 billion to $3 billion		0.80	%
$3 billion and over		0.70	%

Columbia Acorn Select

Average Daily Net Assets	Annual Fee Rate
Up to $700 million		0.85	%
$700 million to $2 billion		0.80	%
$2 billion to $3 billion		0.75	%
$3 billion and over		0.70	%

Columbia Acorn International Select

All Average Daily Net Assets 0.94 %

75

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

Columbia Thermostat Fund

All Average Daily Net Assets 0.10 %

For the year ended December 31, 2007, the Funds' effective investment advisory fee rates were as follows:

Columbia Acorn Fund	0.64	%
Columbia Acorn International	0.76	%
Columbia Acorn USA	0.86	%
Columbia Acorn International Select	0.94	%
Columbia Acorn Select	0.79	%
Columbia Thermostat Fund	0.10	%

>Expense Limit

CWAM has voluntarily agreed to reimburse the ordinary operating expenses (exclusive of Rule 12b-1 service and distribution fees, interest, taxes and extraordinary expenses, but inclusive of custodial charges relating to overdrafts, if any), after giving effect to any balance credits from the Funds' custodian, exceeding 1.45% annually of the average daily net assets for Columbia Acorn International Select's Class A, Class B and Class C shares and 1.35% annually of the average daily net assets for Columbia Acorn Select's Class A, Class B and Class C shares. This arrangement may be modified or terminated by either the Funds or CWAM on 30 days notice.

CWAM has contractually agreed to waive fees and/or reimburse expenses so that the ordinary operating expenses (exclusive of Rule 12b-1 service and distribution fees, interest and fees on borrowings and expenses associated with the Fund's investment in other investment companies, but inclusive of custodial charges relating to overdrafts, if any), after giving effect to any balance credits from the Fund's custodian, will not exceed 0.25% annually of the average daily net assets of Columbia Thermostat Fund's Class A, Class B and Class C shares through April 30, 2008. There is no guarantee that this arrangement will continue thereafter.

Expenses reimbursed by CWAM for Columbia Thermostat Fund for the year ended December 31, 2007, were $315,004.

CWAM provides administrative services and receives an administration fee from the Funds at the following annual rates:

Columbia Acorn Trust

Aggregate Average Daily Net Assets of the Trust:	Annual Fee Rate
Up to $8 billion		0.05	%
$8 billion to $16 billion		0.04	%
$16 billion and over		0.03	%

For the year ended December 31, 2007, each Fund's effective administration fee rate was 0.04% of average daily net assets. CWAM has delegated to Columbia Management Advisors, LLC, an indirect, wholly owned subsidiary of Bank of America ("BOA"), responsibility to provide certain sub-administrative services to the Funds.

Columbia Management Distributors, Inc. ("CMDI"), a wholly owned subsidiary of BOA, is the Funds' principal underwriter and receives no compensation on the sale of Class Z shares.

For the year ended December 31, 2007, Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select and Columbia Thermostat have been advised that CMDI retained $946 in underwriting discounts in connection with redemptions of Class A shares and received CDSCs of $19, $1,700 and $115, in connection with Class A, Class B and Class C share redemptions, respectively.

Each Fund has adopted a Rule 12b-1 (distribution and service) plan which requires it to pay CMDI a monthly service fee equal to 0.25% annually of the average daily net assets attributable to Class A, Class B and Class C shares. The Rule 12b-1 plan also requires each fund to pay CMDI a monthly distribution fee equal to 0.50% and 0.75%, annually, of the average daily net assets attributable to Class B and Class C shares, respectively.

Columbia Management Services, Inc. (the "Transfer Agent"), a wholly owned subsidiary of BOA, provides shareholder services to the Funds. For such services, the Transfer Agent receives a fee, paid monthly, at the annual rate of $17.00 per open account. The Transfer Agent also receives reimbursement for certain out-of-pocket expenses and sub-transfer agency expenses. During the period January 1, 2007 through March 31, 2007, a portion of these fees were contractually waived.

Expenses waived by the Transfer Agent for the year ended December 31, 2007, were as follows:

(in thousands)
Columbia Acorn Fund	$	749
Columbia Acorn International		55
Columbia Acorn USA		67
Columbia Acorn International Select		4
Columbia Acorn Select		101
Columbia Thermostat Fund		11

Certain officers and trustees of the Trust are also officers of CWAM. The Trust makes no direct payments to its officers and trustees who are affiliated with CWAM.

The Board of Trustees appointed a Chief Compliance Officer for the Trust in accordance with federal securities regulations. The Funds, along with other affiliated funds, pay

76

their pro-rata share of the expenses associated with the Office of the Chief Compliance Officer. Those expenses are disclosed separately as "Chief compliance officer expenses" in the Statements of Operations.

The Trust offers a deferred compensation plan for its independent trustees. Under that plan, a trustee may elect to defer all or a portion of his or her compensation. Amounts deferred are retained by the Trust and represent an unfunded obligation of the Trust. The value of amounts deferred is determined by reference to the change in value of Class Z shares of one or more series of the Trust or a money market fund as specified by the trustee. Benefits under the deferred compensation plan are payable when the trustee ceases to be a member of the Board of Trustees.

An affiliate may include any company in which a Fund owns five percent or more of its outstanding voting securities. On December 31, 2007, Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA and Columbia Acorn Select each held five percent or more of the outstanding voting securities of one or more companies. Details of investments in those affiliated companies are presented on pages 31, 32, 41, 49 and 58, respectively.

During the year ended December 31, 2007, the Funds engaged in purchase and sale transactions with funds that have a common investment adviser (or affiliated investment advisers), common directors/trustees, and/or common officers. Those transactions complied with Rule 17a-7 under the Investment Company Act of 1940 and were as follows:

	Purchases		Sales
(in thousands)
Columbia Acorn Fund	$	528	$	—
Columbia Acorn International		11,085		281
Columbia Acorn USA		115		—
Columbia Acorn Select		3,036		—

5.  Borrowing Arrangements

The Trust participates in a $150 million credit facility, which was entered into to facilitate portfolio liquidity. Interest is charged to each participating fund based on its borrowings at a rate per annum equal to the Federal Funds rate plus 0.50%. In addition, a commitment fee of 0.08% per annum of the unutilized line of credit is accrued and apportioned among the participating funds based on their relative net assets. The commitment fee is included in "Other expenses" in the Statements of Operations. No amounts were borrowed by any Fund under this facility for the year ended December 31, 2007.

6.  Investment Transactions

The aggregate cost of purchases and proceeds from sales other than short-term obligations for the year ended December 31, 2007, were:

Columbia Acorn Fund

(in thousands)
Investment securities
Purchases	$	4,733,104
Proceeds from sales		3,798,087

Columbia Acorn International

(in thousands)
Investment securities
Purchases	$	2,001,272
Proceeds from sales		1,409,352

Columbia Acorn USA

(in thousands)
Investment securities
Purchases	$	447,022
Proceeds from sales		341,275

Columbia Acorn International Select

(in thousands)
Investment securities
Purchases	$	175,176
Proceeds from sales		120,111

Columbia Acorn Select

(in thousands)
Investment securities
Purchases	$	1,010,135
Proceeds from sales		374,402

Columbia Thermostat Fund

(in thousands)
Investment securities
Purchases	$	234,732
Proceeds from sales		245,973

7.  Redemption Fees

For the year ended December 31, 2007, the redemption fees imposed by Columbia Acorn International and Columbia Acorn International Select amounted to approximately $303,013 and $30,848, respectively, and are accounted for as additions to paid in capital.

8.   Other

For the year ended December 31, 2007, Columbia Acorn Fund sustained two trading errors. Columbia Acorn Fund sold shares of Enerflex Systems resulting in a loss of $364. Columbia Acorn Fund purchased shares of BioMarin resulting in a loss of $3,750. Additionally, for the year ended December 31, 2007, Columbia Acorn USA sustained one

77

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

trading error. Columbia Acorn USA purchased shares of Cavco Industries at a loss of $5,148.

The Funds were reimbursed by CWAM for the full amount of each loss.

9.   Legal Proceedings

The Trust, CWAM and the Trustees of the Trust (collectively, the "Columbia defendants") are named as defendants in class and derivative complaints that have been consolidated in a Multi-District Action (the "MDL Action") in the federal district court of Maryland. These lawsuits contend that defendants permitted certain investors to market time their trades in certain Columbia Acorn Funds. The MDL Action is ongoing. However, all claims against Columbia Acorn Trust and the independent trustees of the Trust have been dismissed.

The Trust and CWAM are also defendants in a class action lawsuit that alleges, in summary, that the Trust and CWAM exposed shareholders of Columbia Acorn International to trading by market timers by allegedly: (a) failing to properly evaluate daily whether a significant event affecting the value of the Fund's securities had occurred after foreign markets had closed but before the calculation of the Fund's net asset value ("NAV"); (b) failing to implement the Fund's portfolio valuation and share pricing policies and procedures; and (c) failing to know and implement applicable rules and regulations concerning the calculation of NAV (the "Fair Valuation Lawsuit"). The Seventh Circuit ruled that the plaintiffs' state law claims were preempted under federal law resulting in the dismissal of plaintiffs' complaint. Plaintiffs appealed the Seventh Circuit's ruling to the United States Supreme Court. The Supreme Court reversed the Sevent h Circuit's ruling on jurisdictional grounds and the case was ultimately remanded to the state court.

On March 21, 2005, a class action complaint was filed against the Columbia Acorn Trust and CWAM seeking to rescind the CDSC assessed upon redemption of Class B shares of Columbia Acorn Funds due to the alleged market timing of the Columbia Acorn Funds (the "CDSC Lawsuit"). In addition to the rescission of sales charges, plaintiffs seek recovery of actual damages, attorneys' fees and costs. The case had been transferred to the MDL Action in the federal district court of Maryland.

On September 14, 2007, the plaintiffs and the Columbia defendants named in the MDL Action, including the Columbia Funds, entered into a stipulation of settlement with respect to all Columbia-related claims in the MDL Action described above, including the CDSC and Fair Valuation Lawsuits. The settlement is subject to court approval.

CWAM, the Columbia Acorn Funds and the Trustees of the Trust are also defendants in a consolidated lawsuit filed in the federal district court of Massachusetts alleging that CWAM used Fund assets to make undisclosed payments to brokers as an incentive for the brokers to market the Funds over other mutual funds to investors. The complaint alleges CWAM and the Trustees of the Trust breached, along with certain affiliated entities and individuals, certain common law duties and federal laws.

On November 30, 2005, the judge dismissed all claims by plaintiffs and entered final judgment in favor of the defendants. The plaintiffs appealed to the United States Court of Appeals for the First Circuit on December 30, 2005. A stipulation and settlement agreement dated January 19, 2007 was filed in the First Circuit on February 14, 2007, with a joint stipulation of dismissal and motion for remand to obtain district court approval of the settlement. That joint motion was granted and the appeal was dismissed. On March 6, 2007, the case was remanded to the federal district court. The settlement, approved by the federal district court on September 18, 2007, became effective October 19, 2007. Pursuant to the settlement, the funds' adviser and/or its affiliates made certain payments, including plaintiffs' attorneys' fees and costs of notice to class members.

The Trust and CWAM intend to defend these suits vigorously.

As a result of these matters, or any adverse publicity or other developments resulting from them, there may be increased redemptions or reduced sales of Fund shares, which could increase transaction costs or operating expenses, or have other adverse consequences for the Funds. However, based on currently available information, the Columbia Acorn Trust believes that the likelihood that these lawsuits will have a material adverse impact on any fund is remote, and CWAM believes that the lawsuits are not likely to materially affect its ability to provide investment management services to the Funds.

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Report of Independent Registered Public Accounting Firm

To the Board of Trustees and Shareholders of
Columbia Acorn Trust:

In our opinion, the accompanying statements of assets and liabilities, including the statements of investments, and the related statements of operations, changes in net assets and the financial highlights present fairly, in all material respects, the financial position of Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select and Columbia Thermostat Fund (each a series of Columbia Acorn Trust, hereinafter referred to as the "Funds") at December 31, 2007, the results of each of their operations for the year then ended, the changes in each of their net assets for each of the two years in the period then ended and the financial highlights for each of the four years in the period then ended, in conformity with accounting principles generally accepted in the United States of America. These financial statements and financial highlights (hereafter referred to as "financial statements") are the responsibility of the Funds' management; our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these financial statements in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits, which included confirmation of securities at December 31, 2007 by correspondence with the custodian and brokers, provide a reasonable basis for our opinion. The financial highlights of the Funds for the period ended December 31, 2003 wer e audited by other independent auditors whose report dated February 6, 2004 expressed an unqualified opinion on those financial statements.

PricewaterhouseCoopers LLP
Chicago, Illinois
February 20, 2008

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Columbia Acorn Family of Funds

Federal Income Tax Information (in thousands) (unaudited) — Class A, B, C and Z shares

Columbia Acorn Fund

For the fiscal year ended December 31, 2007, the Fund designated long-term capital gains of $1,586,118.

80.06% of the ordinary income distributed by the Fund, for the year ended December 31, 2007, qualified for the corporate dividends received deduction.

For non-corporate shareholders 100.00%, or the maximum amount allowable under the Jobs and Growth Tax Relief Reconciliation Act of 2003, of income distributed by the Fund for the period January 1, 2007 to December 31, 2007 may represent qualified dividend income. Final information will be provided in your 2007 Form 1099-DIV.

Columbia Acorn International

For the fiscal year ended December 31, 2007, the Fund designated long-term capital gains of $458,971. Foreign taxes paid during the fiscal year ended December 31, 2007, amounting to $6,403 ($0.05 per share) are expected to be passed through to shareholders as 100% allowable foreign tax credits on Form 1099-DIV for the year ended December 31, 2007.

For non-corporate shareholders 100.00%, or the maximum amount allowable under the Jobs and Growth Tax Relief Reconciliation Act of 2003, of income distributed by the Fund for the period January 1, 2007 to December 31, 2007 may represent qualified dividend income. Final information will be provided in your 2007 Form 1099-DIV.

Gross income derived from sources within foreign countries amounted to $89,508 ($0.67 per share) for the fiscal year ended December 31, 2007.

Columbia Acorn USA

For the fiscal year ended December 31, 2007, the Fund designated long-term capital gains of $132,635.

Columbia Acorn International Select

Foreign taxes paid during the fiscal year ended December 31, 2007, amounting to $174 ($0.02 per share) are expected to be passed through to shareholders as 100% allowable foreign tax credits on Form 1099-DIV for the year ended December 31, 2007.

Gross income derived from sources within foreign countries amounted to $3,081 ($0.35 per share) for the fiscal year ended December 31, 2007.

5.77% of the ordinary income distributed by the Fund, for the year ended December 31, 2007, qualified for the corporate dividends received deduction.

For non-corporate shareholders 100.00%, or the maximum amount allowable under the Jobs and Growth Tax Relief Reconciliation Act of 2003, of income distributed by the Fund for the period January 1, 2007 to December 31, 2007 may represent qualified dividend income. Final information will be provided in your 2007 Form1099-DIV.

Columbia Acorn Select

For the fiscal year ended December 31, 2007, the Fund designated long-term capital gains of $123,722.

83.92% of the ordinary income distributed by the Fund, for the year ended December 31, 2007, qualified for the corporate dividends received deduction.

For non-corporate shareholders 88.62%, or the maximum amount allowable under the Jobs and Growth Tax Relief Reconciliation Act of 2003, of income distributed by the Fund for the period January 1, 2007 to December 31, 2007 may represent qualified dividend income. Final information will be provided in your 2007 Form1099-DIV.

Columbia Thermostat Fund

For the fiscal year ended December 31, 2007, the Fund designated long-term capital gains of $2,884.

4.71% of the ordinary income distributed by the Fund, for the year ended December 31, 2007, qualified for the corporate dividends received deduction.

For non-corporate shareholders 5.81%, or the maximum amount allowable under the Jobs and Growth Tax Relief Reconciliation Act of 2003, of income distributed by the Fund for the period January 1, 2007 to December 31, 2007 may represent qualified dividend income. Final information will be provided in your 2007 Form 1099-DIV.

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[Excerpt from:]

Columbia Acorn Trust

Management Fee Evaluation of the Senior Officer

Prepared Pursuant to the New York Attorney General's
Assurance of Discontinuance

June 2007

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Introduction

The New York Attorney General's Assurance of Discontinuance ("Order") entered into by Columbia Management Advisors, Inc. ("CMAI") and Columbia Management Distributors, Inc., ("CMDI" and collectively with "CMAI," "CMG") in February 2005, allows CMAI to manage or advise a mutual fund only if the trustees of the fund appoint a "Senior Officer" to perform specified duties and responsibilities. One of these responsibilities includes "managing the process by which proposed management fees (including but not limited to, advisory fees) to be charged the [Funds] are negotiated so that they are negotiated in a manner which is at arms' length and reasonable and consistent with this Assurance of Discontinuance."

This is the first year that the Columbia Acorn Trust and Wanger Advisors Trust (collectively, the "Trusts") and each series thereof (the "Acorn Funds," "WAT Funds" or collectively, the "Funds") have been overseen by the same Board of Trustees ("Board"). The Order provides that this Board must determine the reasonableness of proposed "management fees" by using either an annual competitive bidding process supervised by the Senior Officer or Independent Fee Consultant, or by obtaining "an annual independent written evaluation prepared by or under the direction of the Senior Officer or the Independent Fee Consultant."

"Management fees" are only part of the costs and expenses paid by mutual fund shareholders. The expenses can vary depending upon the class of shares held but usually include: (1) investment management or advisory fees to compensate analysts and portfolio managers for stock research and portfolio management, as well as the cost of operating a trading desk; (2) administrative expenses incurred to prepare registration statements and tax returns, calculate the Funds' net asset values, maintain effective compliance procedures and perform recordkeeping services; (3) transfer agency costs for establishing accounts, accepting and disbursing funds, as well as overseeing trading in Fund shares; (4) custodial expenses incurred to hold the securities purchased by the Funds; and (5) distribution expenses, including commissions paid to brokers that sell the Fund shares to investors.

Columbia Wanger Asset Management, L.P. ("CWAM"), the adviser to the Funds, has proposed that with respect to the Acorn Funds, the Columbia Acorn Trust continue the existing separate agreements governing the first two categories listed above: an advisory agreement governing portfolio management, and an administration agreement governing certain administration and clerical services. Together the fees paid under these two agreements are referred to as "management fees." CWAM proposes that the WAT Funds continue the existing single agreement governing both investment advisory and administrative services. A single management fee would cover both services. Other fund expenses are governed by separate agreements, in particular agreements with two CWAM affiliates: CMDI, the broker-dealer that underwrites and distributes the Funds' shares, and Columbia Management Services, Inc. ("CMSI"), the Funds' transfer agent. In conformity with the terms of the Order, this evaluation, therefore, addresses only the advisory and administrative contracts, and does not extend to the other agreements.

According to the Order, the Senior Officer's evaluation must consider at least the following:

(1)  Management fees (including components thereof) charged to institutional and other clients of CWAM for like services;

(2)  Management fees (including any components thereof) charged by other mutual fund companies for like services;

(3)  Costs to CWAM and its affiliates of supplying services pursuant to the management fee agreements, excluding any intra-corporate profit;

(4)  Profit margins of CWAM and its affiliates from supplying such services;

(5)  Possible economies of scale as the Funds grow larger; and

(6)  The nature and quality of CWAM's services, including the performance of each Fund.

In 2004, the Boards of the two Trusts, then separate groups, each appointed me Senior Officer under the Order. They also determined not to pursue a competitive bidding process and instead, charged me with the responsibility of evaluating the Funds' proposed advisory and administrative fee contracts with CWAM in conformity with the requirements of the Order. This Report is

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an annual evaluation required under the Order. In discharging their responsibilities, the independent Trustees have also consulted independent, outside counsel.

2007 Evaluation

This is the third annual evaluation prepared in connection with the Order. This evaluation follows the same structure as the earlier studies. Some areas are given more emphasis here, while others are given less. Still, the fundamental information gathered for this evaluation is largely the same as past years.

Process and Independence

The objectives of the Order are to insure the independent evaluation of the advisory fees paid by the Funds as well as to insure that all relevant factors are considered. In my view, this contract renewal process has been conducted at arms-length and with independence in gathering, considering and evaluating all relevant data. At the outset of the process, the Trustees sought and obtained from CWAM and CMG a comprehensive compilation of data regarding Fund performance and expenses, adviser profitability, and other information. The Board evaluated this information thoroughly and also explored CWAM's potential capacity restraints. Performance and expense data was obtained from both Morningstar and Lipper, the leading consultants in this area. The rankings prepared by Morningstar and Lipper were independent and not influenced by the adviser. CWAM itself identified what it considers competing funds, and the Trustees considered that data as well.

In the course of its work, the Contract Committee gave careful consideration to the conclusions and recommendations contained in last year's evaluation. The Contract Committee gave particular emphasis to the issue of whether economies of scale were appropriately reflected in the Funds' fee schedules. Last year, the Board sought and CWAM agreed to additional breakpoints for two Funds, Acorn USA and Acorn Select. These breakpoints are above current asset levels, but clearly operate to share economies of scale with Fund shareholders. This year, at the Board's request, CWAM has proposed additional breakpoints for the WAT Funds, and Acorn International Select. This proposal is under consideration by the Board.

My evaluation of the advisory contract was shaped, as it was last year, by my experience as Chief Compliance Officer of the Trusts ("CCO"). As CCO, I report solely to the Board and have no reporting obligation to or employment relationship with CMG or its affiliates, except for administrative purposes. I have commented on compliance matters in evaluating the quality of service provided by CWAM.

This Report, its supporting materials and the data contained in other materials submitted to the Contract Committee of the Board, in my view, provide a thorough factual basis upon which the Board, in consultation with independent counsel as it deems appropriate, may conduct management fee negotiations that are in the best interests of the Funds' shareholders.

The Fee Reductions Mandated under the Order

Under the terms of the Order, CMG agreed to secure certain management fee reductions for the mutual funds advised by its affiliate investment advisers. In some instances, breakpoints were also established. Although neither CWAM nor the Trusts was a party to the Order, CWAM offered and the Board accepted certain advisory fee reductions during 2005. By the terms of the Order, these fees may not be increased before November 30, 2009. I have used these advisory fee levels— as modified last year to add certain breakpoints for Acorn USA and Acorn Select—in this evaluation because they are the fees in the current agreements that CWAM proposes should be continued. Hence, these fee levels are the starting point of an evaluation.

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Conclusions

My review of the data and other material above leads to the following conclusions with respect to the factors identified in the Order.

1.  Performance. The domestic Funds generally have achieved outstanding performance. The Acorn Fund, Acorn USA, Acorn Select, Wanger Select and Wanger US Smaller Companies all rank very favorably against their peers over the past five years. Although Acorn USA and Wanger US Smaller Companies had a difficult year in 2006, these returns are not characteristic of these funds, both of which have shown improved performance during the first quarter of 2007. The international Funds have relatively weaker long term records than the domestic funds, but recently have improved significantly and their one year rankings are excellent. Overall then, performance of the Funds is excellent.

2.  Management Fees relative to Peers. The management fee rankings for several of the Acorn Funds are generally more favorable to shareholders than those of their peer group funds. Management fees do, however, vary by Fund. Acorn Fund is the least expensive and the Acorn USA the most expensive. Acorn Fund is very competitive, while Acorn USA and Acorn Select were ranked by both Lipper and Morningstar at or below the median, and therefore impose higher fees than do the majority of their competitors. The WAT Funds also lag their competitors and impose higher fees than their peers.

3.  Administrative Fees. The Acorn Funds' administrative fee, which is uniform across all Funds, is at a level comparable to or less expensive than the fees imposed by their peers, provides for appropriate services to Funds, and affords breakpoints that lower the fee as assets increase. The WAT Funds pay a single fee for advisory and administrative services and hence do not benefit from administrative fee breakpoints, nor is it possible to assess their administrative costs relative to competitors.

4.  Management Fees relative to Institutional and Other Mutual Fund Accounts. CWAM's focus is on its mutual funds. It does not actively seek to manage separate or institutional accounts. The few institutional accounts it does manage vary in rate structures. Some pay advisory fees commensurate with or higher than the Acorn and WAT Funds. In a few instances, however, institutional accounts pay lower advisory fees than do the Acorn Funds. One particular institutional account is significant in size and has been under CWAM's management for over 25 years.

5.  Costs to CWAM and its Affiliates. CWAM's direct costs do not appear excessive. Overhead and indirect costs allocated to CWAM by its parent organizations, however, are significant and increasing. CWAM's affiliates report operating losses and therefore do not appear to profit from CWAM's advisory agreement with the Funds.

6.  Profit Margins. CWAM's firm-wide, pre-marketing expense profit margins are at the top of the industry, though these comparisons are hampered by limited industry data. High profit margins are not unexpected for firms that manage large, successful funds and have provided outstanding investment performance for investors.

7.  Economies of Scale. Economies of scale do exist at CWAM and will expand as the assets of the Funds get larger. They are, however, only partially reflected in the management fee schedule for the Acorn Funds and not reflected at all in two of the four WAT Funds. Breakpoints above current asset levels have, however, been added to the more expensive funds, Acorn Select and Acorn USA. Nonetheless, if Fund assets continue to grow, under the Funds' current fee schedules, all Fund shareholders might not benefit in a manner generally commensurate with CWAM's increased profits. Management has proposed additional breakpoints for some of the Funds that, if implemented, would result in greater sharing of economies of scale.

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8.  Nature and Quality of Services. This category includes a variety of considerations that are difficult to quantify, yet can have a significant bearing on the performance of the Acorn Funds. Several areas merit comment.

  a.  Capacity. The Funds have continued to grow, posing ever greater challenges in deploying assets effectively. While trends here merit continued monitoring, CWAM appears to be managing assets effectively.

  b.  Compliance. CWAM has a reasonably designed compliance program that protects shareholders.

  c.  Administrative Services. The Funds benefit from a variety of administrative services that are performed by CWAM and CMAI.

9.  Process. In my opinion, the process of negotiating an advisory contract for the Funds has been conducted thoroughly and at arms' length. Further, the Trustees have sufficient information to evaluate management's proposal, and negotiate contract terms that are in the best interests of fund shareholders.

Recommendations
(with respect to the Acorn Funds)

I believe the Trustees should:

1.  Continue to consider additional ways to restructure the advisory fee beyond the current breakpoint schedule to reflect more fully economies of scale.

2.  Continue to monitor CWAM's capacity limitations to insure that the Funds' expanding assets do not impair investment performance.

Robert P. Scales

Senior Vice President,
Chief Legal Officer
and General Counsel

June 18, 2007

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Board Approval of the Advisory Agreement

Columbia Acorn Trust (the "Trust") has an investment advisory agreement (the "Agreement") with Columbia Wanger Asset Management, L.P. ("CWAM") under which CWAM manages the Columbia Acorn Funds (the "Funds"). The trustees of the Trust, more than seventy five percent of whom have never been affiliated with CWAM ("Independent Trustees"), oversee the management of each Fund and, as required by law, determine at least annually whether to continue the Agreement for each Fund.

The Contract Committee of the board of trustees (the "Committee"), which is comprised of six Independent Trustees, makes recommendations to the board regarding any proposed continuation of the Agreement. After the Committee has made its recommendation, the full board determines whether to approve the continuation of the Agreement. In addition, the board considers matters bearing on the Agreement at most of its other meetings throughout the year and meets at least quarterly with the portfolio managers employed by CWAM.

In connection with their most recent consideration of the Agreement for each Fund, the Committee and all trustees received and reviewed a substantial amount of information provided by CWAM in response to requests of the Independent Trustees and their counsel. Throughout their consideration of the Agreement, the Independent Trustees were advised by their independent legal counsel. At each of the meetings at which the Committee or the Independent Trustees considered the Agreement, they met with management and also met separately in executive session with their counsel.

The materials reviewed by the Committee and the trustees included, among other items, (i) information on the investment performance of each Fund and the performance of peer groups of funds and of the Fund's performance benchmarks, (ii) information on each Fund's advisory fees and other expenses, including information comparing the Fund's fees and expenses to those of peer groups of funds and information about any applicable expense limitations and fee "breakpoints," (iii) data on sales and redemptions of Fund shares and (iv) information on the profitability to CWAM and its affiliates of their relationships with the Funds and potential "fall-out" or ancillary benefits that CWAM and its affiliates may receive as a result of their relationships with the Funds. They also considered other information such as (i) CWAM's financial results and financial condition, (ii) each Fund's investment objective and strategies; (iii) the size, edu cation and experience of CWAM's investment staff and its use of technology, external research and trading cost measurement tools, (iv) the allocation of the Funds' brokerage, if any, including allocations to brokers affiliated with CWAM, and the use of "soft" commission dollars to pay for research products and services, (v) the resources devoted to, and the record of compliance with, the Funds' investment policies and restrictions, policies on personal securities transactions and other compliance policies and (vi) the economic outlook generally and for the mutual fund industry in particular. In addition, the trustees conferred with, and reviewed the Management Fee Evaluation (the "Fee Evaluation") prepared by, the Trust's chief compliance officer, who also serves as the Trust's "Senior Officer" as contemplated by the Assurance of Discontinuance dated February 9, 2005 among affiliates of CWAM and the Office of the New York Attorney General. A summary of the Fee Evaluation is included in this report. Throughou t the process, the trustees had the opportunity to ask questions of and request additional materials from CWAM.

On July 17, 2007, the board of trustees unanimously approved continuation of the Agreement through July 31, 2008, with an amendment to the fee schedule as described below. The approval followed Committee meetings held in February, May, June and July 2007.

In considering the continuation of the Agreement, the trustees reviewed and analyzed various factors that they determined were relevant, including the factors described below, none of which by itself was considered dispositive. However, the material factors and conclusions that formed the basis for the trustees' determination to approve the continuation of the Agreement are discussed separately below.

Nature, quality and extent of services. The trustees reviewed the nature, quality and extent of the services of CWAM and its affiliates to the Funds, taking into account the investment objective and strategy of each Fund and the knowledge the trustees gained from their regular meetings with management on at least a quarterly basis. In addition, the trustees reviewed the available resources and key personnel of CWAM and its affiliates, especially those who provide investment management services to the Funds. The trustees also considered other services provided to the Funds by CWAM and its affiliates, such as managing the execution of portfolio transactions and the selection of broker-dealers for those transactions, serving as the Funds' administrator, monitoring adherence to the Funds' investment restrictions, producing shareholder reports, providing s upport services for the board and board committees, communicating with shareholders and overseeing the activities of other service providers, including monitoring compliance

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with various policies and procedures of the Funds and with applicable securities laws and regulations.

The trustees concluded that: the nature, quality and extent of the services provided by CWAM and its affiliates to each Fund were appropriate and consistent with the terms of the Agreement; that the quality of those services had been consistent with or superior to quality norms in the industry; and that the Funds were likely to benefit from the continued provision of those services. They also concluded that each of CWAM and its affiliates currently had sufficient personnel, with appropriate education and experience, to serve the Funds effectively and had demonstrated their continuing ability to attract and retain well qualified personnel.

Performance of the Funds. At various meetings of the board, of the Committee and of the board's investment performance analysis committee, the trustees considered the short-term and longer-term performance of each Fund. They reviewed information comparing each Fund's performance with the performance of the Fund's benchmark and with the performance of comparable funds and peer groups as identified by Lipper Inc. ("Lipper") and Morningstar Associates, LLC ("Morningstar"). They noted that, among the domestic Funds, Columbia Acorn Fund and Columbia Acorn Select had each outperformed its respective benchmark and Lipper and Morningstar peers for the relevant periods. Columbia Acorn USA suffered weak performance compared to its benchmark in 2006 and ranked toward the bottom of its peer group for that period. Notwithstanding that performance, that Fund's perf ormance approximated, or was ahead of, its benchmark for the most recent three, five and ten year periods. The trustees noted that Columbia Thermostat Fund had a limited performance history but was ranked high among its peers by Morningstar (but much less so by Lipper as a result of how Lipper classifies the Fund). The trustees also discussed the performance of the international Funds, noting that both of the international Funds had shown improvement over recent years. During the contract renewal process, the trustees concluded that, although past performance is not necessarily indicative of future results, the Funds' strong overall performance record was an important factor in the their evaluation of the quality of services provided by CWAM under the Agreement.

Costs of Services and Profits Realized by CWAM. At various Committee meetings and other informal meetings, the trustees examined detailed information on fees and expenses of each Fund in comparison to information for other comparable funds provided by Lipper and Morningstar. As noted in the Fee Evaluation, the contractual rates of investment advisory fees and the actual advisory fees for some of the Funds were higher than the median advisory fees of their respective peer groups (particularly with respect to Columbia Acorn USA and Columbia Acorn Select). The trustees also considered the management fees of the Acorn Funds relative to those of the Wanger Advisors Trust funds, a group of funds with similar investment strategies overseen by the same trustees and also managed by CWAM.

The Board and CWAM approved an amendment to the Agreement to establish additional breakpoints for Columbia Acorn International Select at 90 basis points for net asset levels over $500 million. The trustees determined that no other changes were necessary at this time in the fee schedules of the Funds.

The trustees reviewed the Fee Evaluation's analysis of the profitability of CWAM in serving as each Fund's investment adviser and of CWAM and its affiliates in all of their relationships with each Fund, as well as an explanation of the methodology utilized in allocating various expenses among the Funds and other business units. The trustees took into account the methodology used by CWAM in determining compensation payable to portfolio managers and the competitive environment for investment management talent. The trustees recognized that profitability comparisons among fund managers are difficult because very little comparative information is publicly available and the profitability of any manager is affected by numerous factors, including the organizational structure of the particular manager, the types of funds and other accounts it manages, possible other lines of business, the methodology for allocating expenses and the manag er's capital structure and cost of capital.

The trustees also reviewed CWAM's advisory fees for other investment companies, sub-advised funds and other institutional separate accounts, as detailed in the Fee Evaluation. In most instances its institutional separate account fees for various investment strategies were higher than the advisory fees charged to the Funds with corresponding strategies, although for a few accounts, the fees were lower. The trustees noted that CWAM performs significant additional services for the Funds that it does not provide to sub-advised funds or non-mutual fund clients, including administrative services, oversight of the Funds' other service providers, trustee support, regulatory compliance and numerous other services, and that, in servicing the Funds, CWAM assumes many legal risks that it does not assume in servicing

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Board Approval of the Advisory Agreement, continued

many of its other clients. Finally, the trustees considered the financial condition of CWAM as part of the contract renewal process.

The trustees concluded that the rates of advisory fees (as amended for Columbia Acorn International Select) and other compensation payable by the Funds to CWAM and its affiliates were reasonable in relation to the nature and quality of the services to be provided, taking into account the fees charged by other advisers for managing comparable mutual funds with similar strategies and the fees CWAM charges to other clients. The trustees also concluded that the Funds' estimated overall expense ratios were reasonable, taking into account quality of services provided by CWAM and its affiliates and the investment performance of the Funds.

Economies of Scale. The trustees considered information about the potential for CWAM to realize economies of scale as a Fund's assets increase. They noted that the fee schedule for each Fund, other than Columbia Thermostat Fund, which is relatively modest in size, includes reductions in the rate of fees at various asset levels, including the newly established breakpoints for Columbia Acorn International Select. The trustees also noted that the Funds share directly in economies of scale through lower charges on third party service providers based on the combined scale of all of the Funds. Based on the information they reviewed, the trustees concluded that the current fee structure of each Fund was reasonable and that the current rates of fees do reflect a sharing between CWAM and the Funds of economies of scale.

Other Benefits to CWAM. The trustees also reviewed benefits that accrue to CWAM and its affiliates from their relationships with the Funds, as outlined in the Fee Evaluation. They recognized that two affiliates of CWAM separately serve the Funds as transfer agent and distributor, respectively, and that the transfer agent receives compensation from the Funds for services provided and that Columbia Management Distributors, Inc., the Funds' distributor, receives Rule 12b-1 fees, that are paid to broker-dealers. The trustees noted that, other than the services provided by CWAM and its affiliates pursuant to various agreements and the fees to be paid by each Fund therefor, the Funds and CWAM may potentially benefit from their relationship with each other in other ways. The trustees considered CWAM's use of commissions paid by each Fund on its portfolio bro kerage transactions to obtain research products and services benefiting the Fund and/or other clients of CWAM. The trustees determined that CWAM's use of the Funds' "soft" commission dollars to obtain research products and services was consistent with regulatory requirements and guidance then in effect. They also concluded that CWAM benefits from the receipt of proprietary research products and services acquired through commissions paid on portfolio transactions of the Funds and that the Funds benefit from CWAM's receipt of those products and services as well as research products and services acquired through commissions paid by other clients of CWAM. They further concluded that the success of any Fund could attract other business to CWAM or other Funds and that the success of CWAM could enhance its ability to serve the Funds.

After full consideration of the above factors as well as other factors that were instructive in evaluating the Agreement, the trustees, including the Independent Trustees, concluded that the continuation of the Agreement, as amended to revise the fee schedule for Columbia Acorn International Select, was in the best interest of each Fund. On July 17, 2007, the trustees continued the Agreement as so amended through July 31, 2008.

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Board of Trustees and Management of
Columbia Acorn Funds

Each trustee may serve a term of unlimited duration until the end of the calendar year in which the trustee attains the age of 75 years. The trustees appoint their own successors, provided that at least two-thirds of the trustees, after such appointment, have been elected by shareholders. Shareholders may remove a trustee, with or without cause, upon the vote of two-thirds of the Trust's outstanding shares at any meeting called for that purpose. A trustee may be removed, with or without cause, upon the vote of a majority of the trustees. The names of the trustees and officers of Acorn, the date each was first elected or appointed to office, their principal business occupations during at least the last five years, number of portfolios in the fund complex they oversee, and other directorships they hold, are shown below. Each trustee serves in such capacity for each of the six series of Columbia Acorn Trust and for each of the four series of Wanger Advisors Trust.

The address for the trustees and officers of the Trust is Columbia Wanger Asset Management, L.P., 227 West Monroe Street, Suite 3000, Chicago, Illinois 60606. The Funds' Statement of Additional Information includes additional information about the Funds' trustees and officers. You may obtain a free copy of the Statement of Additional Information by writing or calling toll-free:

Columbia Wanger Asset Management, L.P.
Shareholder Services Group
227 W. Monroe, Suite 3000
Chicago IL 60606
1-800-922-6769

Name, Position(s) with Columbia Acorn and Age at December 31, 2007	Year First Elected or Appointed to Office*		Principal Occupation(s) during Past Five Years	Number of Portfolios in Fund Complex Overseen by Trustee/Officer		Other Directorships
Trustees who are not interested persons of Columbia Acorn:
Laura M. Born, 42, Trustee(1)		2007	Adjunct Assistant Professor of Finance, University of Chicago Graduate School of Business; Managing Director – Investment Banking, J.P. Morgan Chase & Co. Incorporated (broker-dealer) 1991-2007.		10	Wanger Advisors Trust
Maureen M. Culhane, 59, Trustee		2007	Retired; Vice President, Goldman, Sachs Asset Management L.P. (investment adviser) 2005; Vice President (Consultant) – Strategic Relationship Management, Goldman, Sachs & Co. 1999-2005; prior thereto, Vice President of Finance and Treasurer, Sara Lee Corporation.		10	Wanger Advisors Trust
Margaret Eisen, 54, Trustee		2002	Managing Director, CFA Institute since 2005; Chief Investment Officer, EAM International LLC (corporate finance and asset management) since 2003; prior thereto, Managing Director, DeGuardiola Advisors (investment bank); formerly Managing Director, North American Equities at General Motors Asset Management, and Director, Worldwide Pension Investments for DuPont Asset Management.		10	Antigenics, Inc. (biotechnology and pharmaceuticals); Wanger Advisors Trust
Jerome Kahn, Jr., 73, Trustee		1987	Portfolio manager and stock analyst and former President, William Harris Investors, Inc. (investment adviser).		10	Wanger Advisors Trust
Steven N. Kaplan, 48, Trustee		1999	Neubauer Family Professor of Entrepreneurship and Finance, Graduate School of Business, University of Chicago.		10	Morningstar, Inc. (provider of independent investment research); Wanger Advisors Trust
David C. Kleinman, 72, Trustee		1972	Adjunct Professor of Strategic Management, University of Chicago Graduate School of Business; business consultant.		10	Sonic Foundry, Inc. (rich media systems and software); Wanger Advisors Trust
Allan B. Muchin, 71, Trustee and Vice Chairman of the Board		1998	Chairman Emeritus, Katten Muchin Rosenman LLP (law firm).		10	Wanger Advisors Trust
Robert E. Nason, 71, Trustee and Chairman of the Board		1998	Consultant and private investor since 1998; formerly Executive Partner, Chief Executive Officer and member of the executive committee of Grant Thornton, LLP (public accounting firm) and member of the policy board of Grant Thornton International.		10	Wanger Advisors Trust
James A. Star, 46, Trustee		2006	President, Longview Asset Management LLC (investment adviser) since 2003, prior thereto, portfolio manager; Vice President, Henry Crown and Company (investment firm); President and Chief Investment Officer, Star Partners (hedge fund) from 1998 to 2003.		10	Wanger Advisors Trust

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Name, Position(s) with Columbia Acorn and Age at December 31, 2007	Year First Elected or Appointed to Office*		Principal Occupation(s) during Past Five Years	Number of Portfolios in Fund Complex Overseen by Trustee/Officer		Other Directorships
Trustees who are not interested persons of Columbia Acorn: (continued)
John A. Wing, 72, Trustee		2002	Partner, Dancing Lion Partners (investment partnership); prior thereto, Frank Wakely Gunsaulus Professor of Law and Finance, and Chairman of the Center for the Study of Law and Financial Markets, Illinois Institute of Technology; formerly Chairman of the Board and Chief Executive Officer of ABN-AMRO Incorporated (formerly named The Chicago Corporation, a financial services firm) and Chief Executive Officer of Market Liquidity Network, LLC.		10	First Chicago Bank and Trust; First Chicago Bancorp; Wanger Advisors Trust
Trustees who are interested persons of Columbia Acorn:
Charles P. McQuaid, 53, Trustee and President(2)		1992	President and Chief Investment Officer, CWAM since October 2003; portfolio manager since 1995 and Director of Research, CWAM and its predecessor from July 1992 through December 2003; Interim Director of International Research, CWAM from October 2003 to December 2004; President of Wanger Advisors Trust since 2003.		10	Wanger Advisors Trust
Ralph Wanger, 72, Trustee(3)		1970	Founder, former President, Chief Investment Officer and portfolio manager, CWAM from July 1992 to September 2003; former President, Columbia Acorn Trust from April 1992 through September 2003; former President, Wanger Advisors Trust 1994 through September 2003; Director, Wanger Investment Company PLC; advisor to CWAM from September 2003 to September 2005.		10	Wanger Advisors Trust
Officers of Columbia Acorn:
Ben Andrews, 41, Vice President		2004	Analyst and portfolio manager, CWAM since 1998; Vice President, Wanger Advisors Trust.		10	None
Michael G. Clarke, 38, Assistant Treasurer		2004	Assistant Treasurer, Wanger Advisors Trust; Chief Accounting Officer and Assistant Treasurer of the Columbia Funds since October 2004; Director of Fund Administration of Columbia Management Advisors, LLC since January 2006; Managing Director of Columbia Management Advisors, LLC from September 2004 to December 2005; Vice President, Fund Administration of Columbia Management Advisors, LLC from June 2002 to September 2004.		10	None
Jeffrey Coleman, 38, Assistant Treasurer		2006	Assistant Treasurer, Wanger Advisors Trust since March 2006; Director of Fund Administration, CWAM since January 2006; Fund Controller, CWAM from October 2004 to January 2006; Vice President of CDC IXIS Asset Management Services, Inc. (investment management) from August 2000 to September 2004.		10	None
J. Kevin Connaughton, 43, Assistant Treasurer		2001	Treasurer and Chief Financial Officer of the Columbia Funds since December 2000; Vice President of Columbia Management Advisors, LLC since April 2003; Assistant Treasurer of Wanger Advisors Trust since 2001; Treasurer and Chief Financial Officer of the Liberty Funds, Stein Roe Funds and Liberty All-Star Funds from December 2000 to December 2006; Treasurer of the Galaxy Funds from September 2002 through November 2005; Treasurer of Columbia Management Multi-Strategy Hedge Fund, LLC from December 2002 through December 2004; and a senior officer of various affiliated entities of the Bank of America Corporation, including other registered and unregistered funds.		10	None

90

Name, Position(s) with Columbia Acorn and Age at December 31, 2007	Year First Elected or Appointed to Office*		Principal Occupation(s) during Past Five Years	Number of Portfolios in Fund Complex Overseen by Trustee/Officer		Other Directorships
Officers of Columbia Acorn: (continued)
P. Zachary Egan, 39, Vice President		2003	Director of International Research, CWAM, since December 2004; portfolio manager, CWAM since 2003; analyst, CWAM since 1999.		10	None
Peter T. Fariel, 50, Assistant Secretary		2006	Associate General Counsel, Bank of America since April 2005; prior thereto, Partner, Goodwin Procter LLP (law firm).		10	None
John Kunka, 37, Assistant Treasurer		2006	Director of Accounting and Operations, CWAM, since 2006; Assistant Treasurer, Wanger Advisors Trust, since 2006; Manager of Mutual Fund Operations, Calamos Advisors, Inc. from 2005 to 2006; prior thereto, Manager of Mutual Fund Administration, Van Kampen Investments.		10	None
Joseph LaPalm, 37, Vice President		2006	Chief Compliance Officer, CWAM since 2005; Vice President, Wanger Advisors Trust since 2006; prior thereto, Compliance Officer, William Blair & Company (investment firm).		10	None
Bruce H. Lauer, 50, Vice President, Secretary and Treasurer		1995	Chief Operating Officer, CWAM since April 2000; Vice President, Treasurer and Secretary, Wanger Advisors Trust; Director, Wanger Investment Company PLC; Director, Banc of America Capital Management (Ireland) Ltd.; Director, Bank of America Global Liquidity Fund PLC.		10	None
Louis J. Mendes, 43, Vice President		2003	Analyst and portfolio manager, CWAM since 2001; Vice President, Wanger Advisors Trust.		10	None
Robert A. Mohn, 46, Vice President		1997	Analyst and portfolio manager, CWAM since August 1992; Director of Domestic Research, CWAM since March 2004; Vice President, Wanger Advisors Trust.		10	None
Christopher Olson, 43, Vice President		2001	Analyst and portfolio manager, CWAM since January 2001; Vice President, Wanger Advisors Trust.		10	None
Robert Scales, 55, Chief Compliance Officer, Chief Legal Officer, Senior Vice President and General Counsel		2004	Chief Compliance Officer, Senior Vice President, Chief Legal Officer and General Counsel, Wanger Advisors Trust since 2004; prior thereto, Associate General Counsel, Grant Thornton LLP.		10	None
Linda Roth-Wiszowaty, 38, Assistant Secretary		2006	Business support analyst, CWAM since April 2007; Assistant Secretary, Wanger Advisors Trust; executive administrator, CWAM since April 2004; prior thereto, executive assistant to the Chief Operating Officer, CWAM.		10	None

*  Dates prior to April 1992 correspond to the date of first election or appointment as a director of officer of The Acorn Fund, Inc., the Trust's predecessor.

(1)  Effective January 1, 2008, Trustee is no longer treated as an "interested person," as defined in the Investment Company Act of 1940, as amended (the "1940 Act"). Prior to January 1, 2008, Trustee was considered an "interested person" of the Trust and of CWAM, as defined in the 1940 Act, as a result of her previous affiliation with J.P. Morgan Chase & Co. Incorporated, a registered broker-dealer that may execute portfolio transactions for or engage in principal transactions with the Funds or other clients or funds advised by CWAM or its affiliates.

(2)  Trustee who is an "interested person" of the Trust and of CWAM, as defined in the 1940 Act, because he is an officer of the Trust and of CWAM.

(3)  Trustee who is treated as an "interested person" of the Trust and of CWAM, as defined in the 1940 Act, because he is a former officer of the Trust and former employee of and consultant to CWAM.

91

Columbia Acorn Family of Funds

Class A, B and C Share Information*

Minimum Initial Investment in
Columbia Acorn International,
Columbia Acorn International
Select and Columbia
Thermostat Fund	$2,500† $1,000 for an IRA
Minimum Initial Investment in Columbia Acorn Fund and Columbia Acorn USA	$75,000†
Minimum Initial Investment in Columbia Acorn Select	$100,000**†
Minimum Subsequent Investment in all Funds	$50
Exchange Fee	None

Columbia Acorn Fund	Class A			Class B			Class C
Management Fees		0.64	%		0.64	%		0.64	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses		0.13	%		0.20	%		0.15	%
Net Expense Ratio		1.02	%		1.59	%		1.79	%
Columbia Acorn International	Class A			Class B			Class C
Management Fees		0.76	%		0.76	%		0.76	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses		0.22	%		0.30	%		0.23	%
Net Expense Ratio		1.23	%		1.81	%		1.99	%
Columbia Acorn USA	Class A			Class B			Class C
Management Fees		0.86	%		0.86	%		0.86	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses		0.14	%		0.24	%		0.17	%
Net Expense Ratio		1.25	%		1.85	%		2.03	%
Columbia Acorn International Select	Class A			Class B			Class C
Management Fees		0.94	%		0.94	%		0.94	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses		0.30	%		0.41	%		0.35	%
Net Expense Ratio		1.49	%		2.10	%		2.29	%
Columbia Acorn Select	Class A			Class B			Class C
Management Fees		0.79	%		0.79	%		0.79	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses		0.15	%		0.25	%		0.19	%
Net Expense Ratio		1.19	%		1.79	%		1.98	%
Columbia Thermostat Fund	Class A			Class B			Class C
Management Fees		0.10	%		0.10	%		0.10	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses***		0.15	%		0.15	%		0.15	%
Net Expense Ratio		0.50	%		1.00	%		1.25	%

    Fees and expenses are for the twelve months ended December 31, 2007, and for Columbia Thermostat Fund include the effect of Columbia Wanger Asset Management's undertaking to waive fees and/or reimburse the Fund for any ordinary operating expenses (exclusive of distribution and service fees, interest and fees on borrowings, and expenses associated with the Fund's investment in other investment companies, but including custodial charges relating to overdrafts, if any), after giving effect to any balance credits from the Fund's custodian, in excess of the annual rate of 0.25% of the average daily net assets. Columbia Thermostat Fund's reimbursement arrangement is contractual through April 30, 2008. The Funds' adviser and/or affiliates had agreed to contractually waive a portion of "other expenses" through March 31, 2007.

  *  Effective February 29, 2008, the funds will no longer offer Class B shares.

  **  Effective June 25, 2007, the board of trustees voted to increase the minimum initial investment for Columbia Acorn Select from $50,000 to $100,000.

  ***  Does not include estimated fees and expenses of 0.70% incurred by the Fund from the underlying funds in which it invests.

  †  Certain exclusions may apply.

92

Columbia Acorn Family of Funds

Investment Adviser

Columbia Wanger Asset Management, L.P.
227 West Monroe Street, Suite 3000
Chicago, Illinois 60606

1-800-922-6769

Distributor

Columbia Management Distributors, Inc.
One Financial Center
Boston, Massachusetts 02111-2621

Transfer Agent, Dividend Disbursing Agent

Columbia Management Services, Inc.
P. O. Box 8081
Boston, Massachusetts 02266-8081

1-800-345-6611

Legal Counsel

Bell, Boyd & Lloyd LLP
Chicago, Illinois

Independent Registered Public Accounting Firm

PricewaterhouseCoopers LLP
Chicago, Illinois

This report, including the schedules of investments, submitted for the general information of the shareholders of Columbia Acorn Trust. This report is not authorized for distribution unless preceded or accompanied by a prospectus. An investor should carefully consider charges and expenses before investing. To obtain a prospectus containing this and other information, please call 800-922-6769 or visit our website (shown below). Please read the prospectus carefully before you invest or send money.

A description of the policies and procedures that the Funds use to determine how to vote proxies and a copy of the Funds' voting record are available (i) without charge, upon request, by calling 800-922-6769 and (ii) on the Securities and Exchange Commission's website at www.sec.gov. Information regarding how the Funds voted proxies relating to portfolio securities during the 12-month period ended June 30, is available from the SEC's website. Information regarding how the Funds voted proxies relating to portfolio securities is also available at http://institutional.columbiamanagement.com.

The Funds file a complete schedule of portfolio holdings with the SEC for the first and third quarters of each fiscal year on Form N-Q. The Funds' Form N-Q is available on the SEC's website at www.sec.gov and may be reviewed and copied at the SEC's Public Reference Room in Washington, D.C. Information on the operation of the Public Reference Room may be obtained by calling 1-800-SEC-0330.

Investors should carefully consider the investment objectives, risks, charges and expenses for any Columbia fund before investing. Contact your Columbia Management representative for a prospectus, which contains this and other important information about the Fund. Read it carefully before investing.

Columbia Management Group, LLC ("Columbia Management") is the investment management division of Bank of America Corporation. Columbia Management entities furnish investment management services and products for institutional and individual investors. Columbia Funds are distributed by Columbia Management Distributors, Inc., member of FINRA, SIPC, part of Columbia Management and an affiliate of Bank of America Corporation. Columbia Wanger Asset Management, L.P. ("CWAM") is an SEC-registered investment adviser and indirect, wholly owned subsidiary of Bank of America Corporation. CWAM is part of Columbia Management.

Find out what's new – visit our web site at:

www.columbiafunds.com

Our e-mail address is:

ServiceInquiries@ColumbiaManagement.com

Shareholders should not include personal information such as account numbers, Social Security numbers or taxpayer identification numbers in e-mail. We are unable to accept account transactions sent via e-mail.

93

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94

Columbia Acorn Family of Funds

Class A, B and C Shares

Annual Report – December 31, 2007

Columbia Management_®

PRESORTED

FIRST-CLASS MAIL

U.S. POSTAGE PAID

HOLLISTON, MA

PERMIT NO. 20

©2008 Columbia Management Distributors, Inc.

One Financial Center, Boston, MA 02111-2621

800-345-6611 www.columbiafunds.com

SHC-43/138992-1207 08/51428

Item 2. Code of Ethics.

(a)The registrant has, as of the end of the period covered by this report, adopted a code of ethics that applies to the registrant’s principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, regardless of whether these individuals are employed by the registrant or a third party.

(b)During the period covered by this report, there were not any amendments to a provision of the code of ethics adopted in
2(a) above.

(c)During the period covered by this report, there were no waivers, including any implicit waivers, from a provision of the code of ethics described in 2(a) above that relates to one or more of the items set forth in paragraph (b) of this item’s instructions.

Item 3. Audit Committee Financial Expert.

The registrant’s Board of Trustees has determined that David C. Kleinman, Robert E. Nason and John A. Wing, each of whom are members of the registrant’s Board of Trustees and Audit Committee, each qualify as an audit committee financial expert.  Mr. Kleinman, Mr. Nason and Mr. Wing are each independent trustees, as defined in paragraph (a)(2) of this item’s instructions.

Item 4. Principal Accountant Fees and Services.

(a) Audit Fees. Aggregate Audit Fees billed by the principal accountant for professional services rendered during the fiscal years ended December 31, 2007 and December 31, 2006 are approximately as follows:

2007		2006
$	210,000	$	208,000

Audit Fees include amounts related to the audit of the registrant’s annual financial statements or services that are normally provided by the accountant in connection with statutory and regulatory filings or engagements for those fiscal years.

(b) Audit-Related Fees. Aggregate Audit-Related Fees billed to the registrant by the principal accountant for professional services rendered during the fiscal years ended December 31, 2007 and December 31, 2006 are approximately as follows:

2007		2006
$	33,000	$	61,400

Audit-Related Fees include amounts for assurance and related services by the principal accountant that are reasonably related to the performance of the audit of the registrant’s financial statements and are not reported in Audit Fees above.  In fiscal years 2007 and 2006, Audit-Related Fees consist of agreed-upon procedures performed for semi-annual shareholder reports or other audit-related additional testing.

During the fiscal years ended December 31, 2007 and December 31, 2006, there were no Audit-Related Fees billed by the registrant’s principal accountant to the registrant’s investment adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser) and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant for an engagement that related directly to the operations and financial reporting of the registrant.

(c) Tax Fees. Aggregate Tax Fees billed by the principal accountant to the registrant for professional services rendered during the fiscal years ended December 31, 2007 and December 31, 2006 are approximately as follows:

2007		2006
$	48,600	$	37,100

Tax Fees incurred in both fiscal years 2007 and 2006 relate to the review of annual tax returns, the review of required shareholder distribution calculations and include amounts for professional services by the principal accountant for tax compliance, tax advice and tax planning.

During the fiscal years ended December 31, 2007 and December 31, 2006, there were no Tax Fees billed by the registrant’s principal accountant to the registrant’s investment adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser) and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant for an engagement that related directly to the operations and financial reporting of the registrant.

(d) All Other Fees. Aggregate All Other Fees billed by the principal accountant to the registrant for professional services rendered during the fiscal years ended December 31, 2007 and December 31, 2006 are as follows:

2007		2006
$	0	$	3,600

All Other Fees include amounts for products and services provided by the principal accountant, other than the services reported in paragraphs (a) through (c) above. In fiscal year 2006, All Other Fees consist of agreed-upon procedures related to the review of the registrant’s anti-money laundering program.

Aggregate All Other Fees billed by the registrant’s principal accountant to the registrant’s investment adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser) and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant for an engagement that related directly to the operations and financial reporting of the registrant during the fiscal years ended December 31, 2007 and December 31, 2006 are approximately as follows:

2007		2006
$	130,000	$	135,600

In both fiscal years 2007 and 2006, All Other Fees consist of professional services rendered for internal control reviews of the registrant’s transfer agent.

(e)(1) Audit Committee Pre-Approval Policies and Procedures

The policy of the registrant’s Audit Committee is to specifically pre-approve (i) all audit and non-audit (including audit related, tax and all other) services provided by the registrant’s independent auditor to the registrant and individual funds (collectively “Fund Services”) and (ii) all non-audit services provided by the registrant’s independent auditor to the funds’ adviser or a control affiliate of the adviser, that relate directly to the funds’ operations and financial reporting (collectively “Fund-related Adviser Services”).  A “control affiliate” is an entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the funds, and the term “adviser” is deemed to exclude any unaffiliated sub-adviser whose role is primarily portfolio management and is sub-contracted or overseen by another investment adviser.

If such Fund Services or Fund-related Adviser Services are required during the period between the Audit Committee’s regularly scheduled meetings, the Chairman of the Audit Committee has the authority to pre-approve the service, with reporting to the full Audit Committee at the next regularly scheduled meeting.

The Audit Committee will waive pre-approval of Fund Services or Fund-related Adviser Services provided that the requirements under paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X are met.

(e)(2) The percentage of services described in paragraphs (b) through (d) of this Item approved pursuant to the “de minimis” exception under paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X during both fiscal years ended December 31, 2007 and December 31, 2006 was zero.

(f) Not applicable.

(g) The aggregate non-audit fees billed by the registrant’s accountant for services rendered to the registrant, and rendered to the registrant’s investment adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser), and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant for the fiscal years ended December 31, 2007 and December 31, 2006 are approximately as follows:

2007		2006
$	211,600	$	237,700

(h) The registrant’s Audit Committee of the Board of Directors has considered whether the provision of non-audit services that were rendered to the registrant’s adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser), and any entity controlling, controlled by, or under common control with the investment adviser that provides ongoing services to the registrant that were not pre-approved pursuant to paragraph (c)(7)(ii) of Rule 2-01 of Regulation S-X, is compatible with maintaining the principal accountant’s independence.

Item 5. Audit Committee of Listed Registrants.

Not applicable.

Item 6. Schedule of Investments

The registrant’s “Schedule I – Investments in securities of unaffiliated issuers” (as set forth in 17 CFR 210.12-12) is included in Item 1 of this Form N-CSR.

Item 7. Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies.

Not applicable.

Item 8. Portfolio Managers of Closed-End Management Investment Companies.

Not applicable.

Item 9. Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers.

Not applicable.

Item 10. Submission of Matters to a Vote of Security Holders.

There have not been any material changes to the procedures by which shareholders may recommend nominees to the registrant’s board of directors, since those procedures were last disclosed in response to requirements of Item 407(c)(2)(iv) of Regulation S-K (as required by Item 22(b)(15) of Schedule 14A) or this Item.

Item 11. Controls and Procedures.

(a)The registrant’s principal executive officer and principal financial officers, based on their evaluation of the registrant’s disclosure controls and procedures as of a date within 90 days of the filing of this report, have concluded that such controls and procedures are adequately designed to ensure that information required to be disclosed by the registrant in Form N-CSR is accumulated and communicated to the registrant’s management, including the principal executive officer and principal financial officer, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure.

(b)There was no change in the registrant’s internal control over financial reporting that occurred during the registrant’s second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting.

Item 12. Exhibits.

(a)(1) Code of ethics required to be disclosed under Item 2 of Form N-CSR attached hereto as Exhibit 99.CODE ETH.

(a)(2) Certifications pursuant to Rule 30a-2(a) under the Investment Company Act of 1940 (17 CFR 270.30a-2(a)) attached hereto as Exhibit 99.CERT.

(a)(3) Not applicable.

(b) Certification pursuant to Rule 30a-2(b) under the Investment Company Act of 1940 (17 CFR 270.30a-2(b)) attached hereto as Exhibit 99.906CERT.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

(registrant)	Columbia Acorn Trust
By (Signature and Title)	/s/ Charles P. McQuaid
	Charles P. McQuaid, President
Date	February 22, 2008

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By (Signature and Title)	/s/ Charles P. McQuaid
	Charles P. McQuaid, President
Date	February 22, 2008
By (Signature and Title)	/s/ Bruce H. Lauer
	Bruce H. Lauer, Treasurer
Date	February 22, 2008

EX-99.CODEETH

Exhibit 99.CODEETH

COLUMBIA WANGER ASSET MANAGEMENT ADVISED FUNDS

CODE OF ETHICS FOR PRINCIPAL EXECUTIVE

AND SENIOR FINANICIAL OFFICERS

I.Covered Officers/Purpose of the Code

This Code of Ethics (the “Code”) for the investment companies within the Columbia Wanger Asset Management fund complex (collectively the “Funds” and each, a “Fund”) applies the Funds’ Principal Executive Officer, Principal Financial Officer, and Principal Accounting Officer (the “Covered Officers”) for the purpose of promoting:

·honest and ethical conduct, including the ethical handling of actual or apparent conflicts of interest between personal and professional relationships;

·full, fair, accurate, timely and understandable disclosure in reports and documents that a Fund files with, or submits to, the Securities and Exchange Commission (“SEC”), and in other public communications made by a Fund;

·compliance with applicable laws and governmental rules and regulations;

·the prompt internal reporting of violations of the Code to an appropriate person or persons identified in the Code; and

·accountability for adherence to the Code.

Each Covered Officer shall adhere to a high standard of business ethics and shall be sensitive to situations that may give rise to actual or apparent conflicts of interest.

II.Administration of the Code

The Code shall be administered by the Columbia Wanger Asset Management Compliance Department.  The Boards of Trustees of the Funds (collectively, the “Board”) shall designate an individual to be primarily responsible for the administration of the Code (the “Code Officer”).  In the absence of the Code Officer, his or her designee shall serve as the Code Officer, but only on a temporary basis.

Each Fund has designated a chief legal officer (the “Chief Legal Officer”) for purposes of the Sarbanes-Oxley Act of 2002 and the rules promulgated thereunder.  The Chief Legal Officer shall assist the Code Officer in administration of this Code.  The Chief Legal Officer is responsible for applying this Code to specific situations in which questions are presented under it (in consultation with Fund counsel, where appropriate) and has the authority to interpret this Code in any particular situation.  However, any waivers sought by

a Covered Officer must be approved by each Audit Committee of the Funds (collectively, the “Audit Committee”).

III.Managing Conflicts of Interest

Overview.  A “conflict of interest” occurs when a Covered Officer’s private interest interferes with the interests of, or his/her service to, a Fund. For example, a conflict of interest would arise if a Covered Officer, or a family member, receives improper personal benefits as a result of the Covered Officer’s position with a Fund.

Certain conflicts of interest arise out of the relationships between Covered Officers and a Fund and already are subject to conflict of interest provisions in the Investment Company Act of 1940 (the “Company Act”) and the Investment Advisers Act of 1940 (the “Advisers Act”).  For example, Covered Officers may not individually engage in certain transactions (such as the purchase or sale of securities or other property) with a Fund because of their status as “affiliated persons” of the Fund.  A Fund’s and its investment adviser’s compliance programs and procedures are designed to prevent, or identify and correct, violations of those provisions.  This Code does not, and is not intended to, repeat or replace those programs and procedures, and such conflicts fall outside of the parameters of this Code.

Although typically not presenting an opportunity for improper personal benefit, conflicts may arise from, or as a result of, the contractual relationship between a Fund and its investment adviser, administrator, pricing and bookkeeping agent and/or transfer agent (each, a “Service Provider”) of which the Covered Officers are also officers or employees.  As a result, this Code recognizes that the Covered Officers will, in the normal course of their duties (whether formally for a Fund or for a Service Provider, or for both), be involved in establishing policies and implementing decisions that will have different effects on the Service Provider and a Fund.  The participation of the Covered Officers in such activities is inherent in the contractual relationship between the Fund and the Service Provider and is consistent with the performance by the Covered Officers of their duties as officers of a Fund.  In addition, it is recognized by the Board that the Covered Officers may also be officers or employees of one or more other investment companies covered by this or other codes.

Other conflicts of interest are covered by the Code, even if such conflicts of interest are not subject to provisions of the Company Act and the Advisers Act.  The following list provides examples of conflicts of interest under the Code, but Covered Officers should keep in mind that these examples are not exhaustive.  The overarching principle is that the personal interest of a Covered Officer should not be placed improperly before the interest of a Fund.

Each Covered Officer must:

·not use personal influence or personal relationships to influence investment decisions or financial reporting by a Fund whereby the Covered Officer or a family member would benefit personally to the detriment of a Fund;

·not cause a Fund to take action, or fail to take action, for the individual personal benefit of the Covered Officer or a family member rather than the benefit of the Fund.

There are some conflict of interest situations that must be approved by the Code Officer, after consultation with the Chief Legal Officer.  Those situations include, but are not limited to,:

·service as director on the board of any public or private company;

·the receipt of any gifts in excess of $100 in the aggregate from a third party that does or seeks to do business with the Funds during any 12-month period;

·the receipt of any entertainment from any company with which a Fund has current or prospective business dealings, unless such entertainment is business-related, reasonable in cost, appropriate as to time and place, and not so frequent as to raise any question of impropriety;

·any material ownership interest in, or any consulting or employment relationship with, any Fund service providers, other than its investment adviser, principal underwriter, administrator or any affiliated person thereof;

·a direct or indirect material financial interest in commissions, transaction charges or spreads paid by a Fund for effecting portfolio transactions or for selling or redeeming shares other than an interest arising from the Covered Officer’s employment, such as compensation or equity ownership.

IV.Disclosure and Compliance

Each Covered Officer shall:

·be familiar with the disclosure requirements generally applicable to the Funds;

·not knowingly misrepresent, or cause others to misrepresent, facts about any Fund to others, whether within or outside the Fund, including to the Fund’s trustees and auditors, and to governmental regulators and self-regulatory organizations;

·to the extent appropriate within his/her area of responsibility, consult with other officers and employees of the Funds and the adviser with the goal of promoting full, fair, accurate, timely and understandable

disclosure in the reports and documents the Funds file with, or submit to, the SEC and in other public communications made by the Funds; and

·promote compliance with the standards and restrictions imposed by applicable laws, rules and regulations.

V.Reporting and Accountability

Each Covered Officer must:

·upon adoption of the Code (or after becoming a Covered Officer), affirm in writing to the Board that he/she has received, read and understands the Code;

·annually affirm to the Board compliance with the requirements of the Code;

·not retaliate against any other Covered Officer or any employee of the Funds or their affiliated persons for reports of potential violations that are made in good faith;

·notify the Chief Legal Officer and the Code Officer promptly if he/she knows of any violation of this Code; and

·respond to the trustee and officer questionnaires circulated periodically in connection with the preparation of disclosure documents for the Funds.

The Code Officer shall maintain records of all activities related to this Code.

The Funds will follow the procedures set forth below in investigating and enforcing this Code:

·The Chief Legal Officer and/or the Code Officer will take all appropriate action to investigate any potential violation reported to him/her;

·If, after such investigation, the Chief Legal Officer and the Code Officer believes that no violation has occurred, the Code Officer will notify the person(s) reporting the potential violation, and no further action is required;

·Any matter that the Chief Legal Officer and/or the Code Officer believes is a violation will be reported to the Audit Committee;

·If the Audit Committee concurs that a violation has occurred, it will inform and make a recommendation to the Board, which will consider appropriate action, which may include review of, and appropriate modifications to, applicable policies and procedures; notification to the Chief Executive Officer of Columbia Management Group; or a recommendation to sanction or dismiss the Covered Officer;

·The Audit Committee will be responsible for granting waivers in its sole discretion;

·Any changes to or waivers of this Code will, to the extent required, be disclosed as provided by SEC rules.

The Chief Legal Officer shall:

·report to the Audit Committee quarterly any approvals provided in     accordance with Section II of this Code; and

·report to the Audit Committee quarterly any violations of, or material issues arising under, this Code.

VI.Other Policies and Procedures

This Code shall be the sole code of ethics adopted by the Funds for the purposes of Section 406 of the Sarbanes-Oxley Act and the rules and forms applicable to registered investment companies thereunder.  Insofar as other polices or procedures of the Funds or the Funds’ Service Providers govern or purport to govern the behavior or activities (including, but not limited to, personal trading activities) of the Covered Officers who are subject to this Code, they are superseded by this Code to the extent that they overlap or conflict with the provisions of this Code.  The Funds’ and their investment advisers’ and principal underwriter’s codes of ethics under Rule 17j-1 under the Company Act and any policies and procedures of the Service Providers are separate requirements applicable to the Covered Officers and are not part of this Code.

VII.  Amendments

All material amendments to this Code must be approved or ratified by the Board, including a majority of independent directors.

VIII. Confidentiality

All reports and records prepared or maintained pursuant to this Code will be considered confidential and shall be maintained and protected accordingly.  Except as otherwise required by law or this Code, such matters shall not be disclosed to anyone other than the Board, the Covered Officers, the Chief Legal Officer, outside audit firms and legal counsel to the Funds, and senior management of Columbia Management Group.

IX.Internal Use

The Code is intended solely for the internal use by the Funds and does not constitute an admission, by or on behalf of any Fund, as to any fact, circumstance, or legal conclusion.

COLUMBIA WANGER ASSET MANAGEMENT ADVISED FUNDS

CODE OF ETHICS FOR PRINCIPAL EXECUTIVE

AND SENIOR FINANICIAL OFFICERS (“CODE”) – AFFIRMATION

I affirm that:

1.Upon the adoption of the Code, I have received, read and understand the Code and have complied with the Code since its adoption on September 23, 2003.

Signature Date

EX-99.CERT

Exhibit 99.CERT

I, Charles P. McQuaid, certify that:

1.I have reviewed this report on Form N-CSR of Columbia Acorn Trust;

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations, changes in net assets, and cash flows (if the financial statements are required to include a statement of cash flows) of the registrant as of, and for, the periods presented in this report;

4.The registrant’s other certifying officers and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant and have:

(a)designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

(b)designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

(c)evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report based on such evaluation; and

(d)disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.The registrant’s other certifying officers and I have disclosed to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

(a)all significant deficiencies and material weaknesses  in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize, and report financial information; and

(b)any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date:	February 22, 2008	/s/ Charles P. McQuaid
		Charles P. McQuaid, President

I, Bruce H. Lauer, certify that:

1.             I have reviewed this report on Form N-CSR of Columbia Acorn Trust;

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations, changes in net assets, and cash flows (if the financial statements are required to include a statement of cash flows) of the registrant as of, and for, the periods presented in this report;

4.The registrant’s other certifying officers and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant and have:

(a)designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

(b)designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

(c)evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report based on such evaluation; and

(d)disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.The registrant’s other certifying officers and I have disclosed to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

(a)all significant deficiencies and material weaknesses  in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize, and report financial information; and

(b)any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date:	February 22, 2008	/s/ Bruce H. Lauer
		Bruce H. Lauer, Treasurer

EX-99.906CERT

Exhibit 99.906CERT

CERTIFICATION PURSUANT TO SECTION 906 OF

THE SARBANES-OXLEY ACT OF 2002

In connection with the Certified Shareholder Report of Columbia Acorn Trust (the “Trust”) on Form N-CSR for the period ending December 31, 2007, as filed with the Securities and Exchange Commission on the date hereof (“the Report”), the undersigned hereby certifies that, to his knowledge:

1.The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2.The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Trust.

Date:  February 22, 2008	/s/ Charles P. McQuaid
	Charles P. McQuaid, President
Date:  February 22, 2008	/s/ Bruce H. Lauer
	Bruce H. Lauer, Treasurer

A signed original of this written statement required by Section 906 of the Sarbanes-Oxley Act of 2002 has been provided to the Registrant and will be retained by the Registrant and furnished to the Securities and Exchange Commission (the “Commission”) or its staff upon request.

This certification is being furnished to the Commission solely pursuant to 18 U.S.C. §1350 and is not being filed as part of the Form N-CSR with the Commission.