January 31, 2013

SUMMARY PROSPECTUS

SIT International Equity Fund (SEITX)

Class A

Before you invest, you may want to review the Fund's prospectus, which contains information about the Fund and its risks. You can find the Fund prospectus and other information about the Fund, including the Fund's Statement of Additional Information, online at seic.com/funds. You can also get this information at no cost by dialing 1-800-DIAL-SEI. The Fund's prospectus and statement of additional information, dated January 31, 2013, as may be supplemented from time to time, are incorporated by reference into this Summary Prospectus.

Investment Goal

Long-term capital appreciation.

Fees and Expenses

The following tables describe the fees and expenses that you may pay if you buy and hold Fund shares.

SHAREHOLDER FEES

(fees paid directly from your investment)	Class A Shares
Redemption Fee (applies to a redemption, or series of redemptions, from a single identifiable source that, in the aggregate, exceeds $50 million within any thirty (30) day period)		0.75	%

ANNUAL FUND OPERATING EXPENSES

(expenses that you pay each year as a percentage of the value of your investment)	Class A Shares
Management Fees		0.51	%
Distribution (12b-1) Fees		None
Other Expenses		0.75	%
Total Annual Fund Operating Expenses		1.26	%

seic.com

SEI / SUMMARY PROSPECTUS

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 redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	1 Year		3 Years		5 Years		10 Years
International Equity Fund — Class A Shares	$	128	$	400	$	692	$	1,523

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 56% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the International Equity Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities. Equity securities may include common stocks, preferred stock, warrants and depositary receipts. The Fund will invest primarily in equity securities of issuers of all capitalization ranges that are located in at least three countries other than the U.S. It is expected that at least 40% of the Fund's assets will be invested outside the U.S. The Fund will invest primarily in companies located in developed countries, but may also invest in companies located in emerging markets. Generally, the Fund will invest less than 20% of its assets in emerging markets. Emerging market countries are those countries that are: (i) characterized as developing or emerging by any of the World Bank, the United Nations, the International Finance Corporation, or the European Bank for Reconstruction and Development; (ii) included in an emerging markets index by a recognized index provider; or (iii) countries with similar developing or emerging characteristics as countries classified as emerging market countries pursuant to sub-paragraph (i) and (ii) above, in each case determined at the time of purchase.

The Fund uses a multi-manager approach, relying upon a number of sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SEI Investments Management Corporation (SIMC), the Fund's adviser.

The Fund may invest in futures contracts, forward contracts and options for hedging purposes, including seeking to manage the Fund's currency exposure to foreign securities and mitigate the Fund's overall risk.

The Fund may purchase shares of exchange-traded funds (ETFs) to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities or other instruments directly.

Principal Risks

Credit Risk — The risk that the issuer of a security or the counterparty to a contract will default or otherwise become unable to honor a financial obligation.

Currency Risk — As a result of the Fund's investments in securities denominated in, and/or receiving revenues in, foreign currencies, the Fund will be subject to currency risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency hedged. In either event, the dollar value of an investment in the Fund would be adversely affected.

Depositary Receipts — Depositary receipts are certificates evidencing ownership of shares of a foreign issuer that are issued by depositary banks and generally trade on an established market. Depositary receipts are subject to many of the risks associated with investing directly in foreign securities, including, among other things, political, social and economic developments abroad, currency movements, and different legal, regulatory and tax environments.

Derivatives Risk — The Fund's use of futures, forward contracts and options is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk and liquidity risk are described below. Market risk is the risk that the market value of an investment may move up and down, sometimes rapidly and unpredictably. Correlation risk is the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. The Fund's use of over-the-counter forward contracts is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative

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SEI / SUMMARY PROSPECTUS

may be difficult to value and/or valued incorrectly. Credit risk is described above. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument.

Equity Market Risk — The risk that stock prices will fall over short or extended periods of time.

Exchange-Traded Funds (ETFs) Risk — The risks of owning shares of an ETF generally reflect the risks of owning the underlying securities the ETF is designed to track, although lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities.

Foreign Investment/Emerging Markets Risk — The risk that non-U.S. securities may be subject to additional risks due to, among other things, political, social and economic developments abroad, currency movements and different legal, regulatory and tax environments. These additional risks may be heightened with respect to emerging market countries since political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

Investment Style Risk — The risk that developed international equity securities may underperform other segments of the equity markets or the equity markets as a whole.

Leverage Risk — The Fund's use of derivatives may result in the Fund's total investment exposure substantially exceeding the value of its portfolio securities and the Fund's investment returns depending substantially on the performance of securities that the Fund may not directly own. The use of leverage can amplify the effects of market volatility on the Fund's share price and may also cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The Fund's use of leverage may result in a heightened risk of investment loss.

Liquidity Risk — The risk that certain securities may be difficult or impossible to sell at the time and the price that the Fund would like. The Fund may have to lower the price, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

Portfolio Turnover Risk — Due to its investment strategy, the Fund may buy and sell securities frequently. This may result in higher transaction costs and additional capital gains tax liabilities.

Small and Medium Capitalization Risk — The risk that small and medium capitalization companies in which the Fund invests may be more vulnerable to adverse business or economic events than larger, more established companies. In particular, small and medium capitalization companies may have limited product lines, markets and financial resources and may depend upon a relatively small management group. Therefore, small capitalization and medium capitalization stocks may be more volatile than those of larger companies. Small capitalization and medium capitalization stocks may be traded over-the-counter or listed on an exchange.

Loss of money is a risk of investing in the Fund.

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SEI / SUMMARY PROSPECTUS

Performance Information

The bar chart and the performance table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year for the past ten calendar years and by showing how the Fund's average annual returns for 1, 5 and 10 years, and since the Fund's inception, compare with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. For current performance information, please call 1-800-DIAL-SEI.

  

Best Quarter: 22.98% (06/30/09)

Worst Quarter: -26.13% (09/30/08)

Average Annual Total Returns (for the periods ended December 31, 2012)

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. Your actual after-tax returns will depend on your tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

International Equity Fund — Class A Shares	1 Year			5 Years			10 Years			Since Inception* (12/20/1989)
Return Before Taxes		16.07	%		(7.32	)%		5.12	%		3.05	%
Return After Taxes on Distributions		15.94	%		(7.41	)%		4.50	%		2.18	%
Return After Taxes on Distributions and Sale of Fund Shares		10.96	%		(5.99	)%		4.48	%		2.33	%
MSCI EAFE Index Return (reflects no deduction for fees, expenses or taxes)		17.32	%		(3.69	)%		8.21	%		3.99	%

* Index returns are shown from December 31, 1989.

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SEI / SUMMARY PROSPECTUS

Management

Investment Adviser. SEI Investments Management Corporation

Sub-Advisers and Portfolio Managers.

Sub-Adviser	Portfolio Manager	Experience with the Fund	Title with Sub-Adviser
Acadian Asset Management LLC	John Chisholm Asha Mehta	Since 2009 Since 2010	Executive Vice President, Chief Investment Officer Vice President, Portfolio Manager
Causeway Capital Management LLC	Sarah H. Ketterer Harry W. Hartford James A. Doyle Jonathan P. Eng Kevin Durkin Conor Muldoon, CFA	Since 2010 Since 2010 Since 2010 Since 2010 Since 2010 Since 2010	Chief Executive Officer President Director Director Director Director
del Rey Global Investors, LLC	Paul Hechmer	Since 2011	Chief Executive Officer, Chief Investment Officer and Managing Member
INTECH Investment Management LLC	Adrian Banner, Ph.D. Joseph Runnels, CFA Vassilios Papathanakos, Ph.D. Phillip Whitman, Ph.D.	Since 2009 Since 2009 Since 2012 Since 2012	Chief Executive Officer and Chief Investment Officer Vice President — Portfolio Management Deputy Chief Investment Officer Director of Research
Neuberger Berman Management LLC	Benjamin Segal, CFA	Since 2010	Managing Director
Schroder Investment Management North America Inc	Virginie Maisonneuve Simon Webber	Since 2010 Since 2010	Head of Global & International Equities Portfolio Manager, Global & International Equities
Tradewinds Global Investors, LLC	Peter L. Boardman	Since 2010	Managing Director, Equity Analyst & Portfolio Manager

Purchase and Sale of Fund Shares

The minimum initial investment for Class A Shares is $100,000 with minimum subsequent investments of $1,000, which may be waived at the discretion of SIMC. You may purchase and redeem shares of a Fund on any day that the New York Stock Exchange (NYSE) is open for business (a Business Day). You may sell your Fund shares by contacting your financial institution or intermediary directly. Financial institutions and intermediaries may redeem Fund shares on behalf of their clients by contacting the Fund's transfer agent (the Transfer Agent) or the Fund's authorized agent, using certain SEI proprietary systems or calling 1-800-858-7233, as applicable.

Tax Information

The distributions made by the Fund are taxable and will be taxed as ordinary income or capital gains. If you are investing through a tax-deferred arrangement, such as a 401(k) plan or individual retirement account, you will generally not be subject to federal taxation on Fund distributions until you begin receiving distributions from your tax-deferred arrangement. You should consult your tax advisor regarding the rules governing your tax-deferred arrangement.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase Fund shares through a broker-dealer or other financial intermediary (such as a bank), the Fund and its related companies may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's website for more information.

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