Class Y Prospectus | SIMT Multi-Strategy Alternative Fund

SIMT Multi-Strategy Alternative Fund

Investment Goal

The Fund allocates its assets among a variety of investment strategies to seek to generate an absolute return with reduced correlation to the stock and bond markets.

Fees and Expenses

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

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

Annual Fund Operating Expenses	Class Y Prospectus SIMT Multi-Strategy Alternative Fund Class Y
Management Fees	1.50%
Distribution (12b-1) Fees	none
Interest Expense on Reverse Repurchase Agreements	0.27%
Dividends on Shorts	0.05%
Remainder of Other Expenses	0.34%
Total Other Expenses	0.66%
Acquired Fund Fees and Expenses (AFFE)	0.49%
Total Annual Fund Operating Expenses	2.65%	[1]

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:

Expense Example	1 Year	3 Years	5 Years	10 Years
Class Y Prospectus | SIMT Multi-Strategy Alternative Fund | Class Y | USD ($)	271	882	1,420	3,012

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 266% of the average value of its portfolio.

Principal Investment Strategies

The Multi-Strategy Alternative Fund employs a strategy intended to generate an absolute (i.e., positive) return in various market cycles with reduced correlation to the stock and bond markets. The Fund allocates its assets among a variety of investment strategies through the use of: (i) affiliated and unaffiliated funds, including open-end funds, closed-end funds and exchange traded funds (Underlying Funds); and/or (ii) one or more investment sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers). In addition, SEI Investments Management Corporation, the Fund's adviser (SIMC or the Adviser), may directly manage a portion of the Fund's portfolio. The Underlying Funds or Sub-Advisers that are employed may apply any of a variety of investment strategies, which may include: (i) directional or tactical strategies, such as long/short equity, long/short credit and global tactical asset allocation; (ii) event driven strategies, such as distressed securities, special situations and merger arbitrage; and (iii) arbitrage strategies, such as fixed income or interest rate arbitrage, convertible arbitrage, pairs trading and equity market neutral.

The Fund will allocate its assets among Underlying Funds and/or Sub-Advisers based on SIMC's analysis of their investment strategies and historical performance as well as SIMC's analysis of the potential for each to perform independently of one another. By allocating its assets in this manner, the Fund will seek to reduce risk, lower volatility and achieve positive returns in various market cycles. Allocation of assets to any one Underlying Fund, Sub-Adviser or strategy will vary based on market conditions. By investing in an Underlying Fund, the Fund becomes a shareholder of that Underlying Fund. Underlying Funds and Sub-Advisers may invest in a broad range of asset classes, securities and other investments to achieve their designated investment strategies, which may include U.S., foreign and emerging markets securities, equity securities of all types and capitalization ranges, investment and non-investment grade fixed income securities (junk bonds) of any duration or maturity issued by corporations or governments, commodities, currencies, warrants, depositary receipts, exchange traded notes and derivative instruments, principally, equity options, futures contracts, options on futures contracts, forward contracts and swap agreements. In addition, the Fund may invest in cash, money market instruments and other short-term obligations to achieve its investment goal. Due to its investment strategy, the Fund may buy and sell securities frequently.

The Fund currently allocates assets to Sub-Advisers pursuant to SIMC's "manager of managers" model, and the Sub-Advisers manage a portion of the Fund's portfolio under the general supervision of SIMC. In addition, SIMC may directly manage a portion of the Fund's assets, which may include allocating assets to investments in Underlying Funds selected by SIMC.

The Fund is intended to be only one component of an investor's broader investment program and is not designed to be a complete investment program. Investors who seek to add an alternative component to their overall investment program may wish to allocate a portion of their investment to the Fund.

Principal Risks

While the Fund seeks to achieve an absolute return with reduced correlation to stock and bond markets, it may not achieve positive returns over short or long term periods. Investment strategies that have historically been non-correlated or have demonstrated low correlations to one another or to stock and bond markets may become correlated at certain times and, as a result, may cease to function as anticipated over either short or long term periods.

The success of the Fund's investment strategy depends both on SIMC's selection of the Underlying Funds and Sub-Advisers and allocating assets to such Underlying Funds and Sub-Advisers. SIMC, an Underlying Fund or a Sub-Adviser may be incorrect in assessing market trends, the value or growth capability of particular securities or asset classes. In addition, the methodology by which SIMC allocates the Fund's assets to the Underlying Funds and Sub-Advisers may not achieve desired results and may cause the Fund to lose money or underperform other comparable mutual funds.

The Fund, Underlying Funds and Sub-Advisers may apply any of a variety of investment strategies and may invest in a broad range of asset classes, securities and other investments to achieve their designated investment strategies. The principal risks of using such investment strategies and making investments in such asset classes, securities and other investments are set forth below. Because an Underlying Fund's use of an investment strategy or investment in an asset class, security or other investment is subject to the same or similar risks as the Fund's use of such strategy or investment in such asset class, security or other investment, the term "the Fund" in the paragraphs below collectively refers to both the Fund and each Underlying Fund.

Equity Market Risk — The risk that the market value of a security may move up and down, sometimes rapidly and unpredictably. Equity market risk may affect a single issuer, an industry, a sector or the equity or bond market as a whole.

Fixed Income 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 decrease liquidity and/or increase volatility in the fixed income markets. In the case of foreign securities, price fluctuations will reflect international economic and political events, as well as changes in currency valuations relative to the U.S. dollar. 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.

Arbitrage Strategies Risk — Arbitrage strategies involve engaging in transactions that attempt to exploit price differences of identical, related or similar securities on different markets or in different forms. The Fund may realize losses or a reduced rate of return if underlying relationships among securities in which it takes investment positions change in an adverse manner or if a transaction is unexpectedly terminated or delayed. Trading to seek short-term capital appreciation can be expected to cause the Fund's portfolio turnover rate to be substantially higher than that of the average equity-oriented investment company.

Directional or Tactical Strategies Risk — Directional or tactical strategies usually use long and short positions, which entail predicting the direction that particular securities or sectors or the overall market might move. Directional or tactical strategies may utilize leverage and hedging. There may be a significant risk of loss if the Fund's judgment is incorrect as to the direction, timing or extent of expected movements of particular securities or sectors or the market as a whole.

Event-Driven Strategies Risk — Event-driven strategies involve making evaluations and predictions about both the likelihood that a particular event in the life of a company will occur and the impact such an event will have on the value of the company's securities. The transaction in which such a company is involved may be unsuccessful, take considerable time (or longer than anticipated) or may result in a distribution of cash or a new security, the value of which may be less than the purchase price of the company's security. If an anticipated transaction does not occur, the Fund may be required to sell its securities at a loss.

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.

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.

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. Although U.S. Government securities are considered to be among the safest investments, they are not guaranteed against price movements due to changing interest rates. 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.

Derivatives Risk — The Fund's use of futures contracts, options, forward contracts and swaps is subject to market risk, leverage risk, correlation risk and liquidity risk. Leverage risk is described above and liquidity risk is described below. Many over-the-counter (OTC) derivative instruments will not have liquidity beyond the counterparty to the instrument. 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 forward contracts and swap agreements is also subject to credit risk and valuation risk. Valuation risk is the risk that the derivative may be difficult to value and/or valued incorrectly. Credit risk is described below. Each of these 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 are in the process of adopting and implementing regulations governing derivatives markets, the ultimate impact of which remains unclear.

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 — Due to its active positions in 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. 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 U.S. or abroad.

Commodity-Linked Securities Risk — Investments in commodity-linked securities may be more volatile and less liquid than direct investments in the underlying commodities themselves. Commodity-related equity returns can also be affected by the issuer's financial structure or the performance of unrelated businesses.

U.S. Government Securities Risk — Although U.S. Government securities are considered to be among the safest investments, they 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.

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.

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.

Distressed Securities Risk — Distressed securities frequently do not produce income while they are outstanding and may require the Fund to bear certain extraordinary expenses in order to protect and recover its investment. Distressed securities are at high risk for default.

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 because political turmoil and rapid changes in economic conditions are more likely to occur in these countries.

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 may acquire.

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 refinancings 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.

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.

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.

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, which may affect the Fund's performance.

Short Sales Risk — A short sale involves the sale of a security that the Fund does not own in the expectation of purchasing the same security (or a security exchangeable therefore) at a later date at a lower price. Short sales expose the Fund to the risk that it will be required to buy the security sold short (also known as "covering" the short position) at a time when the security has appreciated in value, thus resulting in a loss to the Fund that is potentially unlimited. Investment in short sales may also cause the Fund to incur expenses related to borrowing securities. In addition, shorting a future contract may require posting only a margin that may amount to less than the notional exposure of the contract. Such a practice may exacerbate the loss in a case of adverse price action.

Investment Company and Exchange-Traded Funds (ETFs) Risk — When the Fund invests in an investment company, in addition to directly bearing the expenses associated with its own operations, it will bear a pro rata portion of the investment company's expenses. In addition, while the risks of owning shares of an investment company generally reflect the risks of owning the underlying investments of the investment company, the Fund may be subject to additional or different risks than if the Fund had invested directly in the underlying investments. For example, the lack of liquidity in an ETF could result in its value being more volatile than the underlying portfolio securities. Closed-end investment companies issue a fixed number of shares that trade on a stock exchange or over-the-counter at a premium or a discount to their net asset value. As a result, a closed-end fund's share price fluctuates based on what another investor is willing to pay rather than on the market value of the securities in the fund.

Small and Medium Capitalization Companies Risk — The risk that small and medium capitalization companies in which the Fund may invest 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.

Exchange-Traded Notes (ETNs) Risk — The value of an ETN is subject to the credit risk of the issuer. There may not be an active trading market available for some ETNs. Additionally, trading of ETNs may be halted or the ETN may be delisted by the listing exchange.

Depositary Receipts Risk — Depositary receipts, such as American 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.

Warrants Risk — Warrants are instruments that entitle the holder to buy an equity security at a specific price for a specific period of time. Warrants may be more speculative than other types of investments. The price of a warrant may be more volatile than the price of its underlying security, and a warrant may offer greater potential for capital appreciation as well as capital loss. A warrant ceases to have value if it is not exercised prior to its expiration date.

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 Class Y Shares of the Fund by showing changes in the Fund's performance from year to year for the past eight calendar years and by showing how the Fund's average annual returns for 1 and 5 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: 2.73% (12/31/13)
Worst Quarter: -4.38% (12/31/18)

Average Annual Total Returns (for the periods ended December 31, 2018)

The Fund's Class Y Shares commenced operations on April 30, 2015. For full calendar years through December 31, 2015, the performance of the Fund's Class F Shares is shown. The Fund's Class F Shares are offered in a separate prospectus. Because Class Y Shares are invested in the same portfolio of securities, returns for Class Y Shares would have been substantially similar to those of Class F Shares, shown here, and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

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. In the event of negative performance, the Fund's returns after taxes on distributions and sale of Fund shares are calculated assuming that an investor has sufficient capital gains of the same character from other investments to offset any capital losses from the sale of Fund shares. As a result, the Fund's returns after taxes on distributions and sale of Fund shares may exceed the Fund's returns before taxes and/or returns after taxes on distributions.

Average Annual Returns - Class Y Prospectus - SIMT Multi-Strategy Alternative Fund	Label	Average Annual Returns, 1 Year	[1]	Average Annual Returns, 5 Years	[1]	Average Annual Returns, Since Inception	[1]	Average Annual Returns, Inception Date
Class Y	Return Before Taxes	(3.42%)		0.81%		0.99%		Apr. 30, 2015
After Taxes on Distributions | Class Y	Return After Taxes on Distributions	(4.60%)		(0.01%)		0.32%
After Taxes on Distributions and Sale of Fund Shares | Class Y	Return After Taxes on Distributions and Sale of Fund Shares	(1.55%)		0.32%		0.51%
BofA Merrill Lynch 3-Month U.S. Treasury Bills Index (reflects no deduction for fees, expenses or taxes)	BofA Merrill Lynch 3-Month U.S. Treasury Bills Index (reflects no deduction for fees, expenses or taxes)	1.87%	[2]	0.63%	[2]	0.40%	[2]	Mar. 31, 2010

[1] Because the Fund incurred AFFE during the most recent fiscal year, the operating expenses in this fee table will not correlate to the expense ratio in the Fund's financial statements (or the "Financial Highlights" section in the prospectus) because the financial statements include only the direct operating expenses incurred by the Fund, not the indirect costs of investing in other investment companies.

[1] The Fund's Class Y Shares commenced operations on April 30, 2015. For periods prior to April 30, 2015, the performance of the Fund's Class F Shares has been used. Returns for Class Y Shares would have been substantially similar to those of Class F Shares and would have differed only to the extent that Class Y Shares have lower total annual fund operating expenses than Class F Shares.

[2] Although the Fund's performance is benchmarked against the return of the BofA Merrill Lynch 3-Month U.S. Treasury Bills Index, an investment in the Fund is substantially different from an investment in U.S. Treasury bills. Among other things, Treasury bills are backed by the full faith and credit of the U.S. Government and have a fixed rate of return. Investors in Treasury bills do not risk losing their investment, whereas loss of money is a risk of investing in the Fund.