Total

SIIT Ultra Short Duration Bond Fund

SIIT Ultra Short Duration Bond Fund

Investment Goal

Provide higher current income than that typically offered by a money market fund while maintaining a high degree of liquidity and a correspondingly higher risk of principal volatility.

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	SIIT Ultra Short Duration Bond Fund SIIT Ultra Short Duration Bond Fund - Class A
Management Fees	0.15%
Distribution (12b-1) Fees	none
Other Expenses	0.07%
Total Annual Fund Operating Expenses	0.22%

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 and returns may be higher or lower, based on these assumptions your costs would be:

Expense Example	1 Year	3 Years	5 Years	10 Years
SIIT Ultra Short Duration Bond Fund | SIIT Ultra Short Duration Bond Fund - Class A | USD ($)	23	71	124	280

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 affect the Fund's performance. During the most recent fiscal year, the Fund's annualized portfolio turnover rate was 75% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the Ultra Short Duration Bond Fund invests at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade U.S. dollar-denominated debt instruments, including: (i) commercial paper and other corporate obligations; (ii) certificates of deposit, time deposits, bankers' acceptances, bank notes and other obligations of U.S. savings and loan and thrift institutions, U.S. commercial banks (including foreign branches of such banks) and foreign banks that meet certain asset requirements; (iii) U.S. Treasury obligations and obligations issued or guaranteed as to principal and interest by agencies or instrumentalities of the U.S. Government; (iv) mortgage-backed securities; (v) asset-backed securities; (vi) fully-collateralized repurchase agreements involving any of the foregoing obligations; and (vii) U.S. dollar-denominated instruments of foreign issuers. In addition, the Fund may invest in futures contracts, options, swaps and other similar instruments. The primary derivatives used by the Fund are futures contracts, options, interest rate swaps and credit default swaps. The Fund will primarily use futures contracts for hedging purposes to manage the Fund's exposure to interest rate risk. There will be times when the Fund utilizes futures contracts to take an active position to either add or reduce the interest rate sensitivity of the Fund. The Fund will primarily use options and swaps to either mitigate the Fund's overall level of risk or to gain exposure to a particular fixed income security or segment of the fixed income market.

Using a top-down strategy and bottom-up security selection, one or more sub-advisers (each, a Sub-Adviser and collectively, the Sub-Advisers) seeks attractively-valued securities that offer competitive yields and that are issued by issuers that are on a sound financial footing. The Sub-Adviser also considers factors such as the anticipated level of interest rates, relative valuations and yield spreads among various sectors and the duration of the Fund's entire portfolio. Duration measures the price sensitivity of a fixed income security to changes in interest rates. For example, a five-year duration means that the fixed income security will decrease in value by 5% if interest rates rise 1% and increase in value by 5% if interest rates fall 1%. While the Fund may invest in securities with any maturity or duration, the Fund will maintain a portfolio duration of 18 months or less under normal market conditions.

To achieve its investment goal, the Fund may invest in one or more SEI-sponsored funds to pursue its investment strategies in an efficient manner. The Fund may invest in a SEI-sponsored fund only if the SEI-sponsored fund invests in securities and pursues investment strategies that are consistent with the Fund's investment goal and strategy.

The Fund uses a multi-manager approach under the general supervision of SEI Investments Management Corporation (SIMC or the Adviser), the Fund's adviser, allocating its assets among Sub-Advisers using different investment strategies designed to provide current income consistent with the preservation of capital.

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 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.

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.

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

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 a 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.

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.

Commercial Paper Risk — Commercial paper is a short-term obligation with a maturity generally ranging from one to 270 days and is issued by U.S. or foreign companies or other entities in order to finance their current operations. Such investments are unsecured and usually discounted from their value at maturity. The value of commercial paper may be affected by changes in the credit rating or financial condition of the issuing entities and will tend to fall when interest rates rise and rise when interest rates fall. Asset-backed commercial paper may be issued by structured investment vehicles or other conduits that are organized to issue the commercial paper and to purchase trade receivables or other financial assets. The repayment of asset-backed commercial paper depends primarily on the cash collections received from such an issuer's underlying asset portfolio and the issuer's ability to issue new asset-backed commercial paper.

Foreign Investment 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.

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.

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 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.

Repurchase Agreement Risk — Although repurchase agreement transactions must be fully collateralized at all times, they generally create leverage and involve some counterparty risk to the Fund whereby a defaulting counterparty could delay or prevent the Fund's recovery of collateral.

Derivatives Risk — The Fund's use of futures contracts, options, interest rate swaps and credit default swaps is subject to market risk, leverage risk, correlation risk and liquidity risk. Credit risk, 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 forward contracts, credit-linked notes and swaps 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. Market risk is described above. 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.

Investment Company 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 exchange-traded fund could result in its value being more volatile than the underlying portfolio securities.

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.

Opportunity Risk — The risk of missing out on an investment opportunity because the assets necessary to take advantage of it are tied up in other investments.

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.

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.

Leverage Risk — The Fund's use of derivatives and repurchase agreements (which effectively constitute a form of borrowing) 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.

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 seven 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 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.

Best Quarter: 1.19% (9/30/12)
Worst Quarter: -0.04% (6/30/13)
The Fund's total return from January 1, 2019 to June 30, 2019 was 2.19%.

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

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.

Average Annual Returns - SIIT Ultra Short Duration Bond Fund	Label	1 Year	5 Years	Since Inception	Inception Date
SIIT Ultra Short Duration Bond Fund - Class A	Return Before Taxes	1.87%	1.39%	1.38%	Feb. 28, 2011
After Taxes on Distributions | SIIT Ultra Short Duration Bond Fund - Class A	Return After Taxes on Distributions	0.86%	0.71%	0.77%
After Taxes on Distributions and Sale of Fund Shares | SIIT Ultra Short Duration Bond Fund - Class A	Return After Taxes on Distributions and Sale of Fund Shares	1.10%	0.76%	0.79%
Bloomberg Barclays U.S. Treasury Bills 9-12 Month Index (reflects no deduction for fees, expenses or taxes)	Bloomberg Barclays U.S. Treasury Bills 9-12 Month Index (reflects no deduction for fees, expenses or taxes)	1.90%	0.75%	0.59%	Feb. 28, 2011