UBS HIGH YIELD FUND (Prospectus Summary) | UBS HIGH YIELD FUND

UBS High Yield Fund Summary

Investment objective

The Fund seeks to provide high current income, as well as capital growth when

consistent with high current income.

Fees and expenses

These tables describe the fees and expenses that you may pay if you buy and hold

shares of the Fund. You may qualify for a sales charge waiver or discount if you

and your family invest, or agree to invest in the future, at least $100,000 in

the Fund. More information about these and other discounts and waivers, as well

as eligibility requirements for each share class, is available from your

financial advisor and in "Managing your fund account" on page 33 of the Fund's

prospectus and in "Reduced sales charges, additional purchase, exchange and

redemption information and other services" on page 103 of the Fund's statement

of additional information ("SAI").

Shareholder fees (fees paid directly from your investment)

Shareholder Fees UBS HIGH YIELD FUND	CLASS A	CLASS B	CLASS C	CLASS Y
Maximum front-end sales charge (load) imposed on purchases (as a % of offering price)	4.50%	none	none	none
Maximum contingent deferred sales charge (load) (CDSC) (as a % of purchase or sales price, whichever is less)	none	5.00%	0.75%	none
Redemption fee (as a % of amount redeemed within 90 days of purchase, if applicable)	1.00%	1.00%	1.00%	1.00%

Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses UBS HIGH YIELD FUND		CLASS A	CLASS B	CLASS C	CLASS Y
Management fees		0.60%	0.60%	0.60%	0.60%
Distribution and/or service (12b-1) fees		0.25%	1.00%	0.75%	none
Other expenses	[1]	0.52%	0.57%	0.51%	0.43%
Total annual fund operating expenses		1.37%	2.17%	1.86%	1.03%
Less management fee waiver/expense reimbursements		0.17%	0.22%	0.16%	0.08%
Total annual fund operating expenses after management fee waiver/expense reimbursements	[2]	1.20%	1.95%	1.70%	0.95%

Example

This example is intended to help you compare the cost of investing in the Fund

with the cost of investing in other mutual funds. The example assumes that you

invest $10,000 in the Fund for the time periods indicated and then sell all of

your shares at the end of those periods unless otherwise stated. The example

also assumes that your investment has a 5% return each year and that the Fund's

operating expenses remain the same. The costs described in the example reflect

the expenses of the Fund that would result from the contractual fee waiver and

expense reimbursement agreement with the Advisor for the first year

only. Although your actual costs may be higher or lower, based on these

assumptions, your costs would be:

Expense Example UBS HIGH YIELD FUND (USD $)	Expense Example, With Redemption, 1 Year	Expense Example, With Redemption, 3 Years	Expense Example, With Redemption, 5 Years	Expense Example, With Redemption, 10 Years
CLASS A	567	848	1,151	2,008
CLASS B	698	958	1,344	2,096
CLASS C	248	569	991	2,167
CLASS Y	97	320	561	1,252

Expense Example, No Redemption UBS HIGH YIELD FUND (USD $)	Expense Example, No Redemption, 1 Year	Expense Example, No Redemption, 3 Years	Expense Example, No Redemption, 5 Years	Expense Example, No Redemption, 10 Years
CLASS B	198	658	1,144	2,096
CLASS C	173	569	991	2,167

Portfolio turnover

The Fund pays transaction costs, such as commissions, when it buys and sells

securities (or "turns over" its portfolio). A higher portfolio turnover rate may

indicate higher transaction costs and may result in higher taxes when Fund

shares are held in a taxable account. These costs, which are not reflected in

annual fund operating expenses or in the example, affect the Fund's performance.

During the most recent fiscal year, the Fund's portfolio turnover rate was 55%

of the average value of its portfolio.

Principal strategies

Principal investments



The Fund invests in a portfolio of higher yielding, lower-rated debt securities

issued by foreign and domestic companies. Under normal conditions, at least 80%

of the Fund's net assets (plus borrowings for investment purposes, if any) are

invested in fixed income securities that provide higher yields and are

lower-rated. The Fund may invest in fixed income securities of any maturity, but

generally invests in securities having an initial maturity of more than one

year. Investments in fixed income securities may include, but are not limited

to, mortgage-backed and asset-backed securities. Up to 25% of the Fund's total

assets may be invested in foreign securities, which may include securities of

issuers in emerging markets.



The Fund may, but is not required to, use exchange-traded or over-the-counter

derivative instruments for risk management purposes or as part of the Fund's

investment strategies. The derivatives in which the Fund may invest include

options, futures, forward agreements, swap agreements (specifically, interest

rate, total return, currency and credit default swaps), credit-linked securities

and structured investments. All of these derivatives may be used for risk

management purposes, such as hedging against a specific security or currency, or

to manage or adjust the risk profile of the Fund. In addition, all of the

derivative instruments listed above may be used for investment (non-hedging)

purposes to earn income; to enhance returns; to replace more traditional direct

investments; to obtain exposure to certain markets; to establish net short

positions for individual sectors, markets, currencies or securities; or to

adjust the Fund's portfolio duration.



Lower-rated bonds are bonds rated in the lower rating categories of Moody's

Investors Service, Inc. ("Moody's") and Standard & Poor's Ratings Group ("S&P"),

including securities rated Ba or lower by Moody's or BB or lower by S&P.

Securities rated in these categories are considered to be of poorer quality and

predominantly speculative. Bonds in these categories may also be called "high

yield bonds" or "junk bonds."



Management process



The Fund invests in securities that the Advisor expects will appreciate in value

as a result of declines in long-term interest rates or favorable developments

affecting the business or prospects of the issuer which may improve the issuer's

financial condition and credit rating. In selecting securities, the Advisor uses

a quantitative and qualitative credit review process that assesses the ways in

which macroeconomic forces (such as inflation, risk premiums and interest

rates), as well as certain quantitative factors, such as historical operating

results, calculation of credit ratios and expected future outlook, may affect

industry trends. Against the output of this model, the Advisor considers the

viability of specific debt securities, assessing management strength, market

position, competitive environment and financial flexibility.



The Advisor determines optimal sector, security and credit rating weightings

based on its assessment of macro and microeconomic factors. Depending on market

conditions, undervalued securities may be found in different sectors. Therefore,

all investment decisions are interrelated and made using ongoing sector,

security and rating evaluation.

Main risks

All investments carry a certain amount of risk and the Fund cannot guarantee

that it will achieve its investment objective. You may lose money by investing

in the Fund. An investment in the Fund is not a deposit of the bank and is not

insured or guaranteed by the Federal Deposit Insurance Corporation or any other

government agency. Below are some of the specific risks of investing in the

Fund.



Interest rate risk: An increase in prevailing interest rates typically causes

the value of fixed income securities to fall. Changes in interest rates will

likely affect the value of longer-duration fixed income securities more than

shorter-duration securities and higher quality securities more than lower

quality securities. When interest rates are falling, some fixed income securities

provide that the issuer may repay them earlier than the maturity date, and if this

occurs the Fund may have to reinvest these repayments at lower interest rates.



Credit risk: The risk that the Fund could lose money if the issuer or guarantor

of a fixed income security, or the counterparty to or guarantor of a derivative

contract, is unable or unwilling to meet its financial obligations. This risk is

likely greater for lower quality investments than for investments that are

higher quality.



High yield bond risk: The risk that the issuer of bonds with ratings of BB (S&P)

or Ba (Moody's) or below, or deemed of equivalent quality, will default or

otherwise be unable to honor a financial obligation. These securities are

considered to be predominately speculative with respect to an issuer's capacity

to pay interest and repay principal in accordance with the terms of the

obligations. Lower-quality bonds are more likely to be subject to an issuer's

default or downgrade than investment grade (higher-quality) bonds.



Market risk: The risk that the market value of the Fund's investments may

fluctuate, sometimes rapidly or unpredictably, as the stock and bond markets

fluctuate. Market risk may affect a single issuer, industry, or sector of the

economy, or it may affect the market as a whole.



Foreign investing risk: The value of the Fund's investments in foreign

securities may fall due to adverse political, social and economic developments

abroad and due to decreases in foreign currency values relative to the US

dollar. Investments in foreign government bonds involve special risks because

the Fund may have limited legal recourse in the event of default. Also, foreign

securities are sometimes less liquid and more difficult to sell and to value

than securities of US issuers. These risks are greater for investments in

emerging market issuers. In addition, investments in emerging market issuers may

decline in value because of unfavorable foreign government actions, greater

risks of political instability or the absence of accurate information about

emerging market issuers.



Derivatives risk: The value of "derivatives"-so called because their value

"derives" from the value of an underlying asset, reference rate or index-may

rise or fall more rapidly than other investments. When using derivatives for

non-hedging purposes, it is possible for the Fund to lose more than the amount

it invested in the derivative. The risks of investing in derivative instruments

also include market and management risks. Derivatives relating to fixed income

markets are especially susceptible to interest rate risk and credit risk. In

addition, many types of swaps and other non-exchange traded derivatives may be

subject to liquidity risk, credit risk and mispricing or valuation complexity.

These derivatives risks are different from, and may be greater than, the risks

associated with investing directly in securities and other instruments.



Leverage risk associated with financial instruments: The use of financial

instruments to increase potential returns, including derivatives used for

investment (non-hedging) purposes, may cause the Fund to be more volatile than

if it had not been leveraged. The use of leverage may also accelerate the

velocity of losses and can result in losses to the Fund that exceed the amount

originally invested.



Management risk: The risk that the investment strategies, techniques and risk

analyses employed by the Advisor may not produce the desired results.

Performance

The performance information that follows shows the Fund's performance

information in a bar chart and an average annual total returns table. The

information provides some indication of the risks of investing in the Fund by

showing changes in the Fund's performance from year to year and by showing how

the Fund's average annual total returns compare with those of a broad measure of

market performance. Index reflects no deduction for fees, expenses or taxes. The

Fund's past performance (before and after taxes) is not necessarily an

indication of how the Fund will perform in the future. Updated performance for

the Fund is available at http://globalam-us.ubs.com/corpweb/performance.do.



After-tax returns are calculated using the historical highest individual federal

marginal income tax rates and do not reflect the impact of state and local

taxes. Actual after-tax returns depend on an investor's tax situation and may

differ from those shown. In addition, the after-tax returns shown are not

relevant to investors who hold Fund shares through tax-deferred arrangements,

such as 401(k) plans or individual retirement accounts.  After-tax returns for

other classes will vary from the Class Y shares' after-tax returns shown.

UBS High Yield Fund Annual Total Returns of Class Y Shares

Total return January 1 - September 30, 2011: (3.35)%

Best quarter during calendar years shown-2Q 2009: 19.58%

Worst quarter during calendar years shown-4Q 2008: (16.49)%

Average annual total returns (for the periods ended December 31, 2010)

Average Annual Total Returns UBS HIGH YIELD FUND	Average Annual Returns, Label		Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years	Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
CLASS A	Class A Return before taxes		8.73%	5.81%	6.64%	5.40%		Dec. 31, 1998
CLASS B	Class B Return before taxes		8.19%	5.74%		7.23%		Nov. 07, 2001
CLASS C	Class C Return before taxes	[1]	12.72%	6.30%		7.25%		Nov. 07, 2001
CLASS Y	Class Y Return before taxes		14.41%	7.12%	7.43%	6.30%		Sep. 30, 1997
CLASS Y After Taxes on Distributions	Class Y Return after taxes on distributions		10.98%	3.83%	3.75%	2.62%		Sep. 30, 1997
CLASS Y After Taxes on Distributions and Sales	Class Y Return after taxes on distributions and sale of fund shares		9.22%	4.05%	4.02%	2.99%		Sep. 30, 1997
Bofa Merrill Lynch US High Yield Cash Pay Constrained Index	BofA Merrill Lynch US High Yield Cash Pay Constrained Index		15.10%	8.66%	8.84%		[2]

[1] "Other expenses" include "Acquired fund fees and expenses," which were less than 0.01% of the average net assets of the Fund.

[2] The Trust, with respect to the Fund, and UBS Global Asset Management (Americas) Inc., the Fund's investment advisor ("UBS Global AM (Americas)" or the "Advisor"), have entered into a written agreement pursuant to which the Advisor has agreed to waive a portion of its management fees and/or to reimburse expenses (excluding expenses incurred through investment in other investment companies, interest, taxes, brokerage commissions, extraordinary expenses, dividend expense and security loan fees for securities sold short) to the extent necessary so that the Fund's ordinary operating expenses (excluding expenses incurred through investment in other investment companies, interest, taxes, brokerage commissions, extraordinary expenses, dividend expense and security loan fees for securities sold short), through the period ending October 27, 2012, do not exceed 1.20% for Class A shares, 1.95% for Class B shares, 1.70% for Class C shares and 0.95% for Class Y shares. Pursuant to the written agreement, the Advisor is entitled to be reimbursed for any fees it waives and expenses it reimburses for a period of three years following such fee waivers and expense reimbursements to the extent that such reimbursement of the Advisor by the Fund will not cause the Fund to exceed any applicable expense limit that is in place for the Fund.

[1] Prior to September 30, 2003, Class C shares were subject to a maximum front-end sales charge of 1.00%; this front-end sales charge is not reflected in the average annual total returns presented for the Class C shares shown above.

[2] Average annual total returns for the BofA Merrill Lynch US High Yield Cash Pay Constrained Index for the life of each class were as follows: Class A--7.10%; Class B--9.21%; Class C--9.21%; Class Y--6.89%.