January 31, 2021

SUMMARY PROSPECTUS

SIT International Fixed Income Fund (SEFIX)

Class F

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 and annual and semi-annual reports, online at seic.com/fundprospectuses. 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, 2021, as may be supplemented from time to time, are incorporated by reference into this Summary Prospectus.

Paper copies of the Fund's shareholder reports are no longer sent by mail, unless you specifically request them from the Fund or from your financial intermediary, such as a broker-dealer or bank. Shareholder reports are available online and you will be notified by mail each time a report is posted on the Fund's website and provided with a link to access the report online.

You may elect to receive all future reports in paper free of charge. If you invest through a financial intermediary, you can contact your financial intermediary to inform it that you wish to continue receiving paper copies of your shareholder reports. If you invest directly with the Fund, you can inform the Fund that you wish to continue receiving paper copies of your shareholder reports by calling 1-800-DIAL-SEI. Your election to receive reports in paper will apply to all funds held with the SEI Funds or your financial intermediary.

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SEI / SUMMARY PROSPECTUS

Investment Goal

Capital appreciation and current income.

Fees and Expenses

This table describes the fees and expenses that you may pay if you buy, hold, and sell Fund shares. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in this table and examples below.

ANNUAL FUND OPERATING EXPENSES

(expenses that you pay each year as a percentage of the value of your investment)	Class F Shares
Management Fees		0.30	%
Distribution (12b-1) Fees		None
Other Expenses		0.78	%
Total Annual Fund Operating Expenses		1.08	%

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 or hold 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 Fixed Income Fund — Class F Shares	$	110	$	343	$	595	$	1,317

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 64% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the International Fixed Income Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in fixed income securities. The Fund will invest primarily in investment grade foreign government and corporate fixed income securities, as well as foreign mortgage-backed and/or asset-backed fixed income securities, of issuers located in at least three countries other than the U.S. (including, to a lesser extent, emerging market countries). It is expected that at least 40% of the Fund's assets will be invested in non-U.S. securities. Other fixed income securities in which the Fund may invest include: (i) securities issued or guaranteed by the U.S. Government and its agencies and instrumentalities and obligations of U.S. commercial banks, such as certificates of deposit, time deposits, bankers' acceptances and bank notes; (ii) U.S. corporate debt securities and mortgage-backed and asset-backed securities; and (iii) obligations of supranational entities.

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. In selecting investments for the Fund, the Sub-Advisers choose securities issued by corporations and governments located in various countries, looking for opportunities to achieve capital appreciation and gain, as well as current income. There are no restrictions on the Fund's average portfolio maturity or on the maturity of any specific security.

The Sub-Advisers may seek to enhance the Fund's return by actively managing the Fund's foreign currency exposure. In managing the Fund's currency exposure, the Sub-Advisers buy and sell currencies (i.e., take long or short positions) using derivatives, principally futures, foreign currency forward contracts and currency swaps. The Fund may take long and short positions in foreign currencies in excess of the value of the Fund's assets denominated in a particular currency or when the

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Fund does not own assets denominated in that currency. The Fund may also engage in currency transactions in an attempt to take advantage of certain inefficiencies in the currency exchange market, to increase its exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. In managing the Fund's currency exposure from foreign securities, the Sub-Advisers may buy and sell currencies for hedging or for speculative purposes.

The Fund may also invest in futures contracts, forward contracts and swaps for speculative or hedging purposes. Futures contracts, forward contracts and swaps are used to synthetically obtain exposure to the securities identified above or baskets of such securities and to manage the Fund's interest rate duration and yield curve exposure. These derivatives are also used to mitigate the Fund's overall level of risk and/or the Fund's risk to particular types of securities, currencies or market segments. Interest rate swaps are further used to manage the Fund's yield spread sensitivity. When the Fund seeks to take an active long or short position with respect to the likelihood of an event of default of a security or basket of securities, the Fund may use credit default swaps. The Fund may buy credit default swaps in an attempt to manage credit risk where the Fund has credit exposure to an issuer and the Fund may sell credit default swaps to more efficiently gain credit exposure to such security or basket of securities.

The Fund will also invest in securities rated below investment grade (junk bonds). However, in general, the Fund will purchase bonds with a rating of CCC or above. The Fund also invests a portion of its assets in bank loans, which are generally non-investment grade floating rate instruments. The Fund may invest in bank loans in the form of participations in the loans or assignments of all or a portion of the loans from third parties.

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

Market Risk — The prices of the Fund's fixed income securities respond to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments and their agencies. Generally, the Fund's fixed income securities will decrease in value if interest rates rise and vice versa. In a low interest rate environment, risks associated with rising rates are heightened. Declines in dealer market-making capacity as a result of structural or regulatory changes could further decrease liquidity and/or increase volatility in the fixed income markets. Markets for fixed income securities may decline significantly in response to adverse issuer, political, regulatory, market, economic or other developments that may cause broad changes in market value, public perceptions concerning these developments, and adverse investor sentiment or publicity. Similarly, environmental and public health risks, such as natural disasters, epidemics, pandemics or widespread fear that such events may occur, may impact markets adversely and cause market volatility in both the short- and long-term. In response to these events, the Fund's value may fluctuate and/or the Fund may experience increased redemptions from shareholders, which may impact the Fund's liquidity or force the Fund to sell securities into a declining or illiquid market.

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, tax, accounting and audit environments. These additional risks may be heightened with respect to emerging market countries because political turmoil and rapid changes in economic conditions are more likely to occur in these countries. Investments in emerging markets are subject to the added risk that information in emerging market investments may be unreliable or outdated due to differences in regulatory, accounting or auditing and financial record keeping standards, or because less information about emerging market investments is publicly available. In addition, the rights and remedies associated with emerging market investments may be different than investments in developed markets. A lack of reliable information, rights and remedies increase the risks of investing in emerging markets in comparison to more developed markets. In addition, periodic U.S. Government restrictions on investments in issuers from certain foreign countries may require the Fund to sell such investments at inopportune times, which could result in losses to the Fund.

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

Non-Diversified Risk — The Fund is non-diversified, which means that it may invest in the securities of relatively few issuers. As a result, the Fund may be more susceptible to a single adverse economic or political occurrence affecting one or more of these issuers and may experience increased volatility due to its investments in those securities. However, the Fund intends to satisfy the asset diversification requirements under the Internal Revenue Code of 1986, as amended (the Code) for classification as a regulated investment company (RIC).

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Interest Rate Risk — The risk that a rise in interest rates will cause a fall in the value of fixed income securities, including U.S. Government securities, in which the Fund invests. A low interest rate environment may present greater interest rate risk, because there may be a greater likelihood of rates increasing and rates may increase more rapidly.

Duration Risk — The longer-term securities in which the Fund may invest tend to be more volatile than shorter-term securities. A portfolio with a longer average portfolio duration is more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration.

Corporate Fixed Income Securities Risk — Corporate fixed income securities respond to economic developments, especially changes in interest rates, as well as perceptions of the creditworthiness and business prospects of individual issuers.

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.

Foreign Sovereign Debt Securities Risk — The risks that: (i) the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or interest when it becomes due because of factors such as debt service burden, political constraints, cash flow problems and other national economic factors; (ii) governments may default on their debt securities, which may require holders of such securities to participate in debt rescheduling or additional lending to defaulting governments; and (iii) there is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part.

Derivatives Risk — The Fund's use of swaps, futures and forward contracts is subject to market risk, leverage risk, correlation risk and liquidity risk. Market risk is described above, and leverage risk and liquidity risk are described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. 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 swaps and forward contracts is also subject to credit risk and valuation risk. Credit risk is described above. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Each of the above risks could cause the Fund to lose more than the principal amount invested in a derivative instrument. Some derivatives have the potential for unlimited loss, regardless of the size of the Fund's initial investment. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. The Fund's use of derivatives may also increase the amount of taxes payable by shareholders. Both U.S. and non-U.S. regulators have adopted and are in the process of implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

Currency Risk — As a result of the Fund's investments in active positions in currencies and securities or other investments denominated in, and/or receiving revenues in, foreign currencies and the Fund's active management of its currency exposures, 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. Due to the Fund's active positions in currencies, it will be subject to the risk that currency exchange rates may fluctuate in response to, among other things, changes in interest rates, intervention (or failure to intervene) by U.S. or foreign governments, central banks or supranational entities, or by the imposition of currency controls or other political developments in the United States or abroad.

Asset-Backed Securities Risk — Payment of principal and interest on asset-backed securities is dependent largely on the cash flows generated by the assets backing the securities. Securitization trusts generally do not have any assets or sources of funds other than the receivables and related property they own, and asset-backed securities are generally not insured or guaranteed by the related sponsor or any other entity. Asset-backed securities may be more illiquid than more conventional types of fixed-income securities that the Fund acquires.

Below Investment Grade Securities (Junk Bonds) Risk — Fixed income securities rated below investment grade (junk bonds) involve greater risks of default or downgrade and are generally more volatile than investment grade securities because the prospect for repayment of principal and interest of many of these securities is speculative. Because these securities typically offer a higher rate of return to compensate investors for these risks, they are sometimes referred to as "high yield bonds," but there is no guarantee that an investment in these securities will result in a high rate of return.

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

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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 of the security, sell other securities instead or forego an investment opportunity, any of which could have a negative effect on Fund management or performance.

U.S. Government Securities Risk — Although U.S. Government securities are considered to be among the safest investments, they are still subject to the credit risk of the U.S. Government and are not guaranteed against price movements due to changing interest rates. Obligations issued by some U.S. Government agencies are backed by the U.S. Treasury, while others are backed solely by the ability of the agency to borrow from the U.S. Treasury or by the agency's own resources. No assurance can be given that the U.S. Government will provide financial support to its agencies and instrumentalities if it is not obligated by law to do so.

Bank Loans Risk — With respect to bank loans, the Fund will assume the credit risk of both the borrower and the lender that is selling the participation. The Fund may also have difficulty disposing of bank loans because, in certain cases, the market for such instruments is not highly liquid.

Mortgage-Backed Securities Risk — Mortgage-backed securities are affected significantly by the rate of prepayments and modifications of the mortgage loans backing those securities, as well as by other factors such as borrower defaults, delinquencies, realized or liquidation losses and other shortfalls. Mortgage-backed securities are particularly sensitive to prepayment risk, which is described below, given that the term to maturity for mortgage loans is generally substantially longer than the expected lives of those securities; however, the timing and amount of prepayments cannot be accurately predicted. The timing of changes in the rate of prepayments of the mortgage loans may significantly affect the Fund's actual yield to maturity on any mortgage-backed securities, even if the average rate of principal payments is consistent with the Fund's expectation. Along with prepayment risk, mortgage-backed securities are significantly affected by interest rate risk, which is described above. In a low interest rate environment, mortgage loan prepayments would generally be expected to increase due to factors such as refinancing and loan modifications at lower interest rates. In contrast, if prevailing interest rates rise, prepayments of mortgage loans would generally be expected to decline and therefore extend the weighted average lives of mortgage-backed securities held or acquired by the Fund.

Extension Risk — The risk that rising interest rates may extend the duration of a fixed income security, typically reducing the security's value.

Prepayment Risk — The risk that in a declining interest rate environment, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.

LIBOR Replacement Risk — The U.K. Financial Conduct Authority has announced that it intends to stop compelling or inducing banks to submit London Inter-Bank Offered Rate (LIBOR) rates after 2021. The elimination of LIBOR may adversely affect the interest rates on, and value of, certain Fund investments.

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. When the Fund invests in an ETF, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the ETF's expenses.

Investing in the Fund involves risk, and there is no guarantee that the Fund will achieve its investment goal. You could lose money on your investment in the Fund, just as you could with other investments. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

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 performance information shown is based on full calendar years. 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.

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Best Quarter: 3.15% (03/31/16)
Worst Quarter: -3.02% (06/30/15)

Average Annual Total Returns (for the periods ended December 31, 2020)

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 Fixed Income Fund — Class F Shares	1 Year			5 Years			10 Years			Since Inception (9/1/1993)
Return Before Taxes		2.95	%		3.54	%		3.58	%		4.22	%
Return After Taxes on Distributions		2.95	%		2.69	%		2.29	%		2.71	%
Return After Taxes on Distributions and Sale of Fund Shares		1.75	%		2.36	%		2.20	%		2.69	%
Bloomberg Barclays Global Aggregate ex-US Index, Hedged Return (reflects no deduction for fees, expenses or taxes)		3.94	%		4.40	%		4.35	%		5.56	%

Management

Investment Adviser and Portfolio Manager. SEI Investments Management Corporation

Portfolio Manager	Experience with the Fund	Title with Adviser
James Mashiter, CFA	Since 2016	Portfolio Manager

Sub-Advisers and Portfolio Managers.

Sub-Adviser	Portfolio Manager	Experience with the Fund	Title with Sub-Adviser
AllianceBernstein L.P.	Scott DiMaggio, CFA John Taylor Jorgen Kjaersgaard Nicholas Sanders, CFA Eamonn Buckley	Since 2006 Since 2012 Since 2013 Since 2016 Since 2018	Director — Global Fixed Income Portfolio Manager — European Multi-Sector Portfolio Manager — European Credit Portfolio Manager — European and UK Multi-Sector Portfolio Manager — Fixed Income
Colchester Global Investors Ltd	Ian Sims Keith Lloyd, CFA	Since 2017 Since 2017	Chairman and Chief Investment Officer Chief Executive Officer and Deputy Chief Investment Officer
Wellington Management Company LLP	Mark H. Sullivan, CFA	Since 2017	Senior Managing Director and Fixed Income Portfolio Manager

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Purchase and Sale of Fund Shares

The minimum initial investment for Class F Shares is $100,000 with minimum subsequent investments of $1,000. Such minimums may be waived at the discretion of SIMC. You may purchase and redeem shares of the 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 authorized financial institution or intermediary directly. Authorized 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 Investments Company (SEI) or third party systems or by calling 1-800-858-7233, as applicable.

Tax Information

The distributions made by the Fund generally 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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