The Board has approved a change to the Fund’s investment goal in order to permit the Fund to seek “Return characteristics similar to those of high quality bonds.” The Fund’s current investment goal, which is fundamental, is to seek “Return"Return characteristics similar to those of high quality corporate bonds, with a duration range of between nine and fourteen years" to "Return characteristics similar to those of high quality bonds."

Proposal 2:  To approve reclassification of the Fund's investment goal from "fundamental" to "non-fundamental."

The Board, including the Independent Trustees, has approved both the change in the Fund's investment goal and the re-classification of the Fund's investment goal from "fundamental" to "non-fundamental" and unanimously recommends that shareholders of the Fund vote in favor of the proposals.

Proposal 1: Change of the Fund's Investment Goal

The Board has approved a change to the Fund's investment goal in order to permit the Fund to seek "Return characteristics similar to those of high quality bonds." The Fund's current investment goal, which is fundamental, is to seek "Return characteristics similar to those of high quality corporate bonds, with a duration range of between nine and fourteen years.”" SEI Investments Management Corporation, the Fund’sFund's investment adviser (“SIMC”("SIMC" or the “Adviser”"Adviser"), and the Board believe that this change would allow the Fund greater flexibility in its investments by removing the duration restriction imposed by the Fund’sFund's current investment goal. In addition, SIMC and the Board believe that removing “corporate”"corporate" from the current investment goal would provide further flexibility to the Fund.

SIMC does not believe that the changes in the Fund’sFund's investment goal will significantly change the nature of the Fund’sFund's portfolio or the types of investments that the Fund will make. The Fund’sFund's principal investment strategies will not be changing as a result of the change to the Fund’sFund's investment goal, if approved. Rather, the proposed change to the Fund’sFund's current investment goal would remove the duration limitation that currently restricts the Fund’sFund's investments. This broadening of the Fund’sFund's investment universe is expected to provide the Fund with increased investment opportunities, greater diversification opportunities for the Fund’sFund's portfolio, the potential for lower risk and lower volatility, the potential for increased investment returns, and the ability to more closely align with its benchmark index.index (which has a more dynamic duration range than the Fund's current investment goal permits). SIMC believes that the Fund’sFund's new investment goal, if approved, would be more consistent with similar registered funds, including other series of the Trust.

If the shareholders of the Fund do not approve the proposals, the Fund’sFund's current investment goal would remain in place and the investment goal would continue to be classified as “fundamental.”"fundamental." SIMC believes that this is not in the best interests of shareholders because the Fund’sFund's current investment goal unnecessarily imposes a duration restriction on the Fund’sFund's investments that cannot be changed without undertaking the lengthy and costly process of holding a shareholder meeting. Further, this limitation is not imposed as a fundamental limitation on many similar registered funds, which could limit the Fund’sFund's ability to attract and retain assets compared to similar registered funds. There can be no assurance that the Fund will achieve its investment goal.

The Board recommends that you vote “FOR”"FOR" the change of the Fund’sFund's investment goal.

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Adjournment

If a quorum is not present at the Meeting, or if a quorum is present but sufficient votes in favor of a Proposal are not received by the time scheduled for the Meeting, the persons named as proxies may propose one or more adjournments of the Meeting for a period or periods to permit further solicitation of proxies. If quorum is present at the Meeting, any such adjournment will require the affirmative vote of a majority of the votes cast on the question, in person or by proxy, at the session of the Meeting to be adjourned. The persons named as proxies will vote in favor of such adjournment those proxies that they are entitled to vote in favor of a Proposal. They will vote against any such adjournment those proxies required to be voted against a Proposal. The Fund will bear the costs of any additional solicitation and any adjourned sessions.

Voting

Shares represented by duly executed proxies will be voted at the Meeting in accordance with the instructions given. However, if no instructions are specified on the proxy with respect to a Proposal, shares will be voted FOR the approval of the Proposal and in accordance with the judgment of the persons appointed as proxies upon any other matter that may properly come before the Meeting. If you wish to participate in the Meeting, you may submit the proxy card included with this Proxy Statement or attend in person. Your vote is important no matter how many shares you own. You can vote easily and quickly by telephone, Internet, mail or in person at the Meeting. Should you require additional information regarding the proxy or replacement proxy cards, you may contact SIIT at 1-800-DIAL-SEI.

Revocation

A shareholder may revoke a previously submitted proxy at any time prior to the Meeting by (i) a written revocation, which must be signed and include the shareholder’sshareholder's name and account number, received by the Secretary of the Trust at One Freedom Valley Drive, Oaks, PA 19456; (ii) properly executing a later-dated proxy; or (iii) attending the Meeting and voting in person.

OTHER INFORMATION

Solicitation of Proxies, Payment of Expenses

The solicitation of proxies is being made on behalf of the Board, on behalf of the Fund. The Fund has retained Broadridge Financial Solutions, Inc. (the “Proxy Solicitor”"Proxy Solicitor") to aid in the solicitation. The costs of retaining the Proxy Solicitor and other expenses incurred in connection with the solicitation of proxies will be paid by the Fund. The anticipated cost associated with the solicitation of proxies by the Proxy Solicitor is approximately $4,000 plus any reasonable out-of-pocket expenses incurred by the Proxy Solicitor. Proxies may be solicited by mail, electronically, by telephone, fax, in person or by other means, and representatives of the Proxy Solicitor, SIIT, SIMC, the Administrator and SEI may participate in the solicitation of proxies.

The Fund will pay all expenses related to conducting this proxy, including, but not limited to, preparation, printing and mailing of this Proxy Statement and its enclosures, legal fees, and solicitation costs. SIIT estimates these costs to be approximately $40,000. The payment of such fees will be considered an

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Shareholders Sharing the Same Address

If two or more shareholders share the same address, only one copy of this Proxy Statement is being delivered to that address, unless SIIT has received contrary instructions from one or more of the shareholders at that shared address. Upon written or oral request, SIIT will deliver promptly a separate copy of this Proxy Statement to a shareholder at a shared address. Please note that each shareholder will receive a separate proxy card, regardless of whether he or she resides at a shared address. Please call 1-800-DIAL-SEI or forward a written request to SIIT, One Freedom Valley Drive, Oaks, Pennsylvania 19456 if you would like to (1) receive a separate copy of this Proxy Statement; (2) receive your annual reports, semi-annual reports or proxy statements separately in the future; or (3) request delivery of a single copy of annual reports, semi-annual reports or proxy statements if you are currently receiving multiple copies at a shared address.

Shareholder Proposals

SIIT is organized as a business trust under the laws of the Commonwealth of Massachusetts. As such, SIIT is not required to, and does not, have annual meetings, except to the extent that such meetings are required under the 1940 Act or state law. Shareholders who wish to submit proposals for inclusion in the proxy statement for a future shareholder meeting should send their written proposals to the Secretary of SIIT at One Freedom Valley Drive, Oaks, PA 19456 within a reasonable time before such meeting. Submission of a proposal does not necessarily mean that such proposal will be included in SIIT’sSIIT's proxy statement since inclusion in the proxy statement is subject to compliance with certain federal regulations.

Communications with the Board

Shareholders wishing to submit written communications to the Board should send their communications to the Secretary of SIIT at One Freedom Valley Drive, Oaks, PA 19456. Any such communications received will be reviewed by the Board at its next regularly scheduled meeting.

Shares Outstanding

The Fund only offers Class A Shares, with each share being entitled to one vote, and each fractional share is entitled to a proportional fractional vote. As of the Record Date, the net assets (rounded to the nearest dollar) and the approximate number of shares issued and outstanding (rounded to the nearest whole share) for the Fund were as follows:

Beneficial Ownership of Shares and Security Ownership of Management

Appendix A to this Proxy Statement contains information about the beneficial ownership by shareholders of five percent (5%) or more of the Fund’sFund's outstanding shares as of the Record Date.

The Trust has delegated to SIMC the authority to vote proxies on the securities held in the Fund’sFund's portfolios. Accordingly, SIMC will have voting authority if any shares of the Fund are held by another SEI Fund. The Trust has been advised by SIMC that any shares of the Fund over which SIMC has voting power will be voted in the same proportion as the vote of all other shareholders of the Fund. As of the

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Other Business

The Board does not intend to present any other business at the Meeting. If any other matter may properly come before the Meeting, or any adjournment(s) thereof, the persons named in the accompanying proxy card intend to vote, act, or consent thereunder in accordance with their best judgment at that time with respect to such matters unless such proxy contains specific restrictions to the contrary.

Annual Report to Shareholders

For a free copy of the Fund’sFund's most recent annual report and most recent semi-annual report succeeding the annual report, shareholders of the Fund may call 1-800-DIAL-SEI or write to the Fund at One Freedom Valley Drive, Oaks, PA 19456.

The Trustees, including the Independent Trustees,
recommend that shareholders of the Fund approve the Proposals.

PROMPT EXECUTION AND RETURN OF THE ENCLOSED PROXY CARD IS REQUESTED. A SELF-ADDRESSED, POSTAGE-PAID ENVELOPE IS ENCLOSED FOR YOUR CONVENIENCE. YOU MAY ALSO VOTE BY TELEPHONE OR ON THE INTERNET. ANY UNMARKED PROXIES WITHOUT INSTRUCTIONS TO THE CONTRARY WILL BE VOTED IN FAVOR OF APPROVAL OF THE PROPOSALS.

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