Class A Prospectus | SIIT HIGH YIELD BOND FUND

SIIT HIGH YIELD BOND FUND

Investment Goal

Total return.

Fund 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 A Prospectus SIIT HIGH YIELD BOND FUND SIIT HIGH YIELD BOND FUND - CLASS A
Management Fees		0.49%
Distribution (12b-1) Fees		none
Other Expenses		0.07%
Acquired Fund Fees and Expenses (AFFE)		0.01%
Total Annual Fund Operating Expenses	[1]	0.57%

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 (USD $)	1 Year	3 Years	5 Years	10 Years
Class A Prospectus SIIT HIGH YIELD BOND FUND SIIT HIGH YIELD BOND FUND - CLASS A	58	183	318	714

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 72% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the High Yield Bond Fund will invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in high yield fixed income securities. The Fund will invest primarily in fixed income securities rated below investment grade (junk bonds), including corporate bonds and debentures, convertible and preferred securities, zero coupon obligations and tranches of collateralized debt obligations (CDOs) and collateralized loan obligations (CLOs).

The Fund uses a multi-manager approach, relying upon a number of Sub-Advisers with differing investment philosophies to manage portions of the Fund's portfolio under the general supervision of SIMC. Assets of the Fund not allocated to Sub-Advisers are managed directly by SIMC. In managing the Fund's assets, the Sub-Advisers and, to the extent applicable, SIMC, select securities that offer a high current yield as well as total return potential. The Fund's securities are diversified as to issuers and industries. The Fund's average weighted maturity may vary and will generally not exceed ten years. There is no limit on the maturity or on the credit quality of any security.

As noted above, the Fund will invest primarily in securities rated BB, B, CCC, CC, C and D. However, it may also invest in non-rated securities or securities rated investment grade (AAA, AA, A and BBB). The Fund may also invest in ETFs to gain exposure to a particular portion of the market while awaiting an opportunity to purchase securities directly. The Fund may also invest a portion of its assets in bank loans, which are generally non-investment grade (junk bond) floating rate instruments. The Fund may invest in bank loans in the form of participations in the loans (participations) and assignments of all or a portion of the loans from third parties (assignments).

Principal Risks

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

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 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.

CDOs and CLOs Risk — CDOs and CLOs are securities backed by an underlying portfolio of debt and loan obligations, respectively. CDOs and CLOs issue classes or "tranches" that vary in risk and yield and may experience substantial losses due to actual defaults, decrease of market value due to collateral defaults and removal of subordinate tranches, market anticipation of defaults and investor aversion to CDO and CLO securities as a class. The risks of investing in CDOs and CLOs depend largely on the tranche invested in and the type of the underlying debts and loans in the tranche of the CDO or CLO, respectively, in which the Fund invests. CDOs and CLOs also carry risks including, but not limited to, interest rate risk and credit risk, which are described below. When the Fund invests in CDOs or CLOs, in addition to directly bearing the expenses associated with its own operations, it may bear a pro rata portion of the CDO's or CLO's expenses.

Convertible and Preferred Securities — Convertible and preferred securities have many of the same characteristics as stocks, including many of the same risks. In addition, convertible bonds may be more sensitive to changes in interest rates than stocks. Convertible bonds may also have credit ratings below investment grade, meaning that they carry a higher risk of failure by the issuer to pay principal and/or interest when due.

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.

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.

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

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 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.

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.

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

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.

Prepayment Risk — The risk that with declining interest rates, 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.

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

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 years and by showing how the Fund's average annual returns for 1 year, 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: 22.79% (06/30/09)

Worst Quarter: -20.84% (12/31/08)

The Fund's total return from January 1, 2013 to June 30, 2013 was 2.75%.

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.

Average Annual Returns Class A Prospectus SIIT HIGH YIELD BOND FUND	Label	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, Since Inception		Average Annual Returns, Inception Date
SIIT HIGH YIELD BOND FUND - CLASS A	Return Before Taxes	16.89%	10.45%	9.27%	[1]	Dec. 05, 2005
After Taxes on Distributions SIIT HIGH YIELD BOND FUND - CLASS A	Return After Taxes on Distributions	13.89%	6.94%	5.85%	[1]
After Taxes on Distributions and Sale of Fund Shares SIIT HIGH YIELD BOND FUND - CLASS A	Return After Taxes on Distributions and Sale of Fund Shares	10.85%	6.74%	5.80%	[1]
BofA Merrill Lynch U.S. High Yield Constrained Index Return (reflects no deduction for fees, expenses or taxes)	BofA Merrill Lynch U.S. High Yield Constrained Index Return (reflects no deduction for fees, expenses or taxes)	15.55%	10.14%	9.11%	[1]	Dec. 31, 2005

[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] Index returns are shown from December 31, 2005.