Institutional Shares:    FPOXX

Before you invest, you may want to review the Goldman Sachs Financial Square Prime Obligations Fund’s (the “Fund”) Prospectus, which contains more information about the Fund and its risks. You can find the Fund’s Prospectus and other information about the Fund, including the Statement of Additional Information (“SAI”) and most recent annual reports to shareholders, online at www.gsamfunds.com/summaries. You can also get this information at no cost by calling 800-621-2550 or by sending an e-mail request to gs-funds-document-requests@gs.com. The Fund’s Prospectus and SAI, both dated December 29, 2016, are incorporated by reference into this Summary Prospectus.

INVESTMENT OBJECTIVE

The Fund seeks to maximize current income to the extent consistent with the preservation of capital and the maintenance of liquidity by investing exclusively in high quality money market instruments.

FEES AND EXPENSES OF THE FUND

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund.

SHAREHOLDER FEES (fees paid directly from your investment)

	Institutional     Shares
Maximum Sales Charge (Load) Imposed on Purchases	None
Maximum Deferred Sales Charge (Load)	None
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	None
Redemption Fees	None
Exchange Fees	None

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

	Institutional Shares
Management Fees		0.21	%
Other Expenses		0.02	%
Total Annual Fund Operating Expenses		0.23	%
Fee Waiver1		(0.05	)%
Total Annual Fund Operating Expenses After Fee Waiver		0.18	%

¹  The Investment Adviser has agreed to not impose a portion of the Management Fee equal annually to 0.045% of the Fund’s average daily net assets through at least December 29, 2017, and prior to such date the Investment Adviser may not terminate the arrangement without the approval of the Board of Trustees.

EXPENSE 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 Institutional Shares of the Fund for the time periods indicated and then redeem all of your Institutional 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 (except that the Example incorporates the fee waiver arrangement for only the first year). 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
Institutional Shares	$        18	$        69	$        124	$        288

PRINCIPAL STRATEGY

The Fund pursues its investment objective by investing in securities issued or guaranteed by the United States or certain U.S. government agencies or instrumentalities (“U.S. Government Securities”), obligations of banks (which may exceed 25% of its total assets), commercial paper and other short-term obligations of U.S. companies, states, municipalities and other entities, and repurchase agreements. The Fund may also invest in U.S. dollar-denominated obligations of foreign banks, foreign companies and foreign governments. The Fund may, but does not currently intend to, invest in Euro certificates of deposit. The Fund may not invest more than 25% of its total assets in the securities of any one foreign government.

The Fund intends to be an “institutional money market fund” under Rule 2a-7 under the Investment Company Act of 1940, as

2        SUMMARY PROSPECTUS — GOLDMAN SACHS FINANCIAL SQUARE PRIME OBLIGATIONS FUND — INSTITUTIONAL SHARES

amended (the “Investment Company Act”). Although the Fund is a money market fund, the net asset value (“NAV”) of the Fund’s shares will fluctuate with changes in the values of its portfolio securities.

Under Rule 2a-7, the Fund may invest only in U.S. dollar-denominated securities that meet certain risk-limiting conditions relating to portfolio quality, maturity, diversification and liquidity.

PRINCIPAL RISKS OF THE FUND

You could lose money by investing in the Fund. Because the share price of the Fund will fluctuate, when you sell your shares they may be worth more or less than what you originally paid for them. The Fund may impose a fee upon the sale of your shares or may temporarily suspend your ability to sell shares if the Fund’s liquidity falls below required minimums because of market conditions or other factors. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Fund’s sponsor has no legal obligation to provide financial support to the Fund, and you should not expect that the sponsor will provide financial support to the Fund at any time. The Fund should not be relied upon as a complete investment program. There can be no assurance that the Fund will achieve its investment objective.

Banking Industry Risk. An adverse development in the banking industry (domestic or foreign) may affect the value of the Fund’s investments more than if the Fund were not invested to such a degree in the banking industry. Banks may be particularly susceptible to certain economic factors such as interest rate changes, adverse developments in the real estate market, fiscal, regulatory and monetary policy and general economic cycles.

Credit/Default Risk. An issuer or guarantor of a security held by the Fund, or a bank or other financial institution that has entered into a repurchase agreement with the Fund, may default on its obligation to pay interest and repay principal or default on any other obligation. Additionally, the credit quality of securities may deteriorate rapidly, which may impair the Fund’s liquidity and cause significant deterioration in NAV.

Floating NAV Risk. The Fund does not maintain a stable NAV per share. The value of the Fund’s shares will be calculated to four decimal places and will fluctuate with changes in the values of the Fund’s portfolio securities. When you sell your shares, they may be worth more or less than what you originally paid for them. This may result in a capital gain or loss.

Foreign Risk. Foreign securities may be subject to risk of loss because of more or less foreign government regulation, less public information and less economic, political and social stability in the countries in which the Fund invests. The imposition of sanctions, confiscations, trade restrictions (including tariffs) and other government restrictions by the United States and other governments, or from problems in share registration, settlement or custody, may also result in losses. In addition, the Fund will be subject to the risk that an issuer of foreign sovereign debt or the government authorities that control the repayment of the debt may be unable or unwilling to repay the principal or interest when due.

Interest Rate Risk. When interest rates increase, the Fund’s yield will tend to be lower than prevailing market rates, and the market value of its securities or instruments may also be adversely affected. The risks associated with increasing interest rates are heightened given that interest rates are near historic lows, but may be expected to increase in the future with unpredictable effects on the markets and the Fund’s investments. A low interest rate environment poses additional risks to the Fund, because low yields on the Fund’s portfolio holdings may have an adverse impact on the Fund’s ability to provide a positive yield to its shareholders, pay expenses out of Fund assets, or minimize the volatility of the Fund’s NAV per share. Fluctuations in interest rates may also affect the liquidity of fixed income securities and instruments held by the Fund.

Large Shareholder Transactions Risk. The Fund may experience adverse effects when certain large shareholders purchase or redeem large amounts of shares of the Fund. Such large shareholder redemptions may cause the Fund to sell portfolio securities at times when it would not otherwise do so, which may negatively impact the Fund’s NAV and liquidity. Similarly, large Fund share purchases may adversely affect the Fund’s performance to the extent that the Fund is delayed in investing new cash and is required to maintain a larger cash position than it ordinarily would. These transactions may also accelerate the realization of taxable income to shareholders if such sales of investments resulted in gains, and may also increase transaction costs. In addition, a large redemption could result in the Fund’s current expenses being allocated over a smaller asset base, leading to an increase in the Fund’s expense ratio.

Liquidity Risk. The Fund may make investments that are illiquid or that may become less liquid in response to market developments or adverse investor perceptions. Illiquid investments may be more difficult to value. The liquidity of portfolio securities can deteriorate rapidly due to credit events affecting issuers or guarantors, such as a credit rating downgrade, or due to general market conditions or a lack of willing buyers. An inability to sell one or more portfolio positions, or selling such positions at an unfavorable time and/or under unfavorable conditions, can increase the volatility of the Fund’s NAV per share. Liquidity risk may also refer to the risk that the Fund will not be able to pay redemption proceeds within the allowable time period because of unusual market conditions, an unusually high volume of redemption requests, or other reasons. Liquidity risk may be the result of, among other things, the reduced number and capacity of traditional market participants to make a market in fixed income securities or the lack of an active market. The potential for liquidity risk may be magnified by a rising interest rate environment or other circumstances where investor redemptions from money market and other fixed income mutual funds may be higher than normal, potentially causing increased supply in the market due to selling activity.

Market Risk. The market value of the securities in which the Fund invests may go up or down in response to the prospects of individual companies, particular sectors or governments and/or general economic conditions throughout the world due to increasingly interconnected global economies and financial markets.

3        SUMMARY PROSPECTUS — GOLDMAN SACHS FINANCIAL SQUARE PRIME OBLIGATIONS FUND — INSTITUTIONAL SHARES

Municipal Securities Risk. Municipal securities are subject to credit/default risk, interest rate risk and certain additional risks. The Fund may be more sensitive to adverse economic, business or political developments if it invests a substantial portion of its assets in the debt securities of similar projects (such as those relating to education, health care, housing, transportation, and utilities), industrial development bonds, or in particular types of municipal securities (such as general obligation bonds, private activity bonds and moral obligation bonds). Generally, municipalities continue to experience difficulties in the current economic and political environment.

U.S. Government Securities Risk. The U.S. government may not provide financial support to U.S. government agencies, instrumentalities or sponsored enterprises if it is not obligated to do so by law. Certain U.S. Government Securities, including securities issued by the Federal National Mortgage Association (“Fannie Mae”), Federal Home Loan Mortgage Corporation (“Freddie Mac”) and Federal Home Loan Banks, are neither issued nor guaranteed by the U.S. Treasury and, therefore, are not backed by the full faith and credit of the United States. The maximum potential liability of the issuers of some U.S. Government Securities held by the Fund may greatly exceed their current resources, including any legal right to support from the U.S. Treasury. It is possible that issuers of U.S. Government Securities will not have the funds to meet their payment obligations in the future.

PERFORMANCE

The bar chart and table below provide an indication of the risks of investing in the Fund by showing: (a) changes in the performance of the Fund’s Institutional Shares from year to year; and (b) the average annual total returns of the Fund’s Institutional Shares. The Fund’s past performance is not necessarily an indication of how the Fund will perform in the future. Performance reflects fee waivers and/or expense limitations in effect during the periods shown. Updated performance information is available at no cost at www.gsamfunds.com/performance or by calling 1-800-621-2550.

AVERAGE ANNUAL TOTAL RETURN

For the period ended December 31, 2015	1 Year	5 Years	10 Years	Since Inception
Institutional Shares (Inception 3/8/90)	0.07%	0.07%	1.35%	3.21%

PORTFOLIO MANAGEMENT

Goldman Sachs Asset Management, L.P. is the investment adviser for the Fund (the “Investment Adviser” or “GSAM”).

BUYING AND SELLING FUND SHARES

Generally, Institutional Shares may be purchased only through certain intermediaries that have a relationship with Goldman, Sachs & Co. (“Goldman Sachs”), including banks, trust companies, brokers, registered investment advisers and other financial institutions (“Intermediaries”). The minimum initial investment requirement imposed upon Intermediaries for the purchase of Institutional Shares is generally $10 million, and there is no minimum imposed upon additional investments. Intermediaries may, however, impose a minimum amount for initial and additional investments in Institutional Shares, and may establish other requirements such as a minimum account balance.

You may purchase and redeem (sell) shares of the Fund on any business day through an Intermediary.

TAX INFORMATION

The Fund’s distributions are taxable, and will be taxed as ordinary income or capital gains, unless you are investing through a tax-deferred arrangement, such as a 401(k) plan or an individual retirement account. Investments through tax-deferred arrangements may become taxable upon withdrawal from such arrangements.

PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL  INTERMEDIARIES

If you purchase the Fund through an Intermediary, the Fund and/or 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 Intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your Intermediary’s website for more information.

4        SUMMARY PROSPECTUS — GOLDMAN SACHS FINANCIAL SQUARE PRIME OBLIGATIONS FUND — INSTITUTIONAL SHARES

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