Exhibit (13)(m)

                                 GATEWAY FUND

                             DELEGATION AGREEMENT

   AGREEMENT made the 16th day of February, 2008, by and between Gateway
Investment Advisers, LLC, a Delaware limited liability company (the "Manager"),
and Natixis Asset Management Advisors, L.P., a Delaware limited partnership
(the "Administrator").

                                  WITNESSETH:

   WHEREAS, Gateway Investment Advisers, LLC (the "Manager") has entered into
an Advisory Agreement dated February 16, 2008 (the "Advisory Agreement") with
the Gateway Trust, a Massachusetts business trust (the "Fund"), relating to the
provision of portfolio management services to the Gateway Fund (the "Series");

   WHEREAS, pursuant to the Advisory Agreement the Manager may delegate any or
all of its responsibilities thereunder with respect to the provision of
Administrative Services (as defined in the Advisory Agreement); and

   WHEREAS, the Manager desires to retain the Administrator to render such
Administrative Services in the manner and on the terms set forth in this
Agreement.

   NOW, THEREFORE, in consideration of the premises and covenants hereinafter
contained, the parties agree as follows:

(1) Administrative Services. The Administrator shall provide the Series the
    following services:

     (a) office space in such place or places as may be agreed upon from time
         to time by the Fund and the Manager, and all necessary office
         supplies, facilities and equipment;

     (b) necessary executive and other personnel for managing the affairs of
         the Series (exclusive of those related to and to be performed under
         contract for custodial, transfer, dividend and plan agency services by
         the entity or entities selected to perform such services and exclusive
         of any managerial functions described in the Advisory Agreement); and

     (c) compensation, if any, of trustees of the Fund who are directors,
         officers or employees of the Manager, any sub-adviser or any
         administrator or of any affiliated person (other than a registered
         investment company) of the Manager, any Sub-Adviser or any
         administrator.

(2) Expenses. Except for expenses specifically assumed or agreed to be paid by
    the Administrator pursuant hereto, the Administrator shall not be liable
    for any organizational, operational or business expenses of the Fund
    including, without limitation, (a) interest and taxes, (b) brokerage
    commissions and other costs in connection

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   with the purchase or sale of securities or other investment instruments with
   respect to the Series, and (c) custodian fees and expenses. The
   Administrator will pay its own expenses incurred in furnishing the services
   to be provided by it pursuant to this Agreement. Neither the Administrator
   nor any affiliated person thereof shall be entitled to any compensation from
   the Fund with respect to service by any affiliated person of the
   Administrator as an officer or trustee of the Fund.

(3) Compensation of the Administrator. The parties acknowledge that the
    Administrator shall receive no compensation for the services rendered,
    facilities furnished and expenses borne by the Administrator hereunder;
    provided, however, the parties acknoweldge that the Administrator shall be
    compensated under the Administrative Services Agreement, dated as of
    January 3, 2005, as from time to time amended, by and between the
    Administrator (formerly IXIS Asset Management Advisors, L.P.) and Natixis
    Funds Trust I, Natixis Funds Trust II, Natixis Funds Trust III, Natixis
    Funds Trust IV, Natixis Cash Management Trust, Loomis Sayles Funds I,
    Loomis Sayles Funds II, Hansberger International Series, and the Fund.

(4) Non-Exclusivity. The Manager agrees that the services of the Administrator
    are not to be deemed exclusive and that the Administrator and its
    affiliates are free to provide similar services and other services to
    others, so long as its services hereunder are not impaired thereby.

(5) Liability. In the absence of willful misfeasance, bad faith or gross
    negligence on the part of the Administrator, or reckless disregard of its
    obligations and duties hereunder, the Administrator shall not be subject to
    any liability to the Manager, the Fund, the Series, to any shareholder of
    the Series or to any other person, firm or organization, for any act or
    omission in the course of, or connected with, rendering services hereunder.

(6) Effective Date and Termination. This Agreement shall become effective as of
    the date of its execution, and

     (a) unless otherwise terminated, this Agreement shall become effective as
         of the date first above written and shall continue in effect for two
         years from the date of execution, and from year to year thereafter so
         long as such continuance is specifically approved at least annually by
         the Board of Trustees of the Fund;

     (b) this Agreement may be terminated at any time without the payment of
         any penalty by either party on not less than sixty (60) days' written
         notice to the other party;

     (c) this Agreement shall automatically terminate in the event of its
         assignment; and

     (d) this Agreement shall automatically terminate upon any termination of
         the Advisory Agreement.

   Termination of this Agreement pursuant to this Section 6 shall be without
   the payment of any penalty.

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(7)General.

    (a)The Administrator may perform its services through any employee, officer
       or agent of the Administrator or its affiliates.

    (b)If any term or provision of this Agreement or the application thereof to
       any person or circumstances is held to be invalid or unenforceable to
       any extent, the remainder of this Agreement or the application of such
       provision to other persons or circumstances shall not be affected
       thereby and shall be enforced to the fullest extent permitted by law.

    (c)In accordance with Regulation S-P, if non-public personal information
       regarding either party's customers or consumers is disclosed to the
       other party in connection with this Agreement, the party receiving such
       information will not disclose or use that information other than as
       necessary to carry out the purposes of this Agreement.

    (d)This Agreement shall be governed by and interpreted in accordance with
       the laws of the Commonwealth of Massachusetts.

NATIXIS ASSET MANAGEMENT ADVISORS,L.P.
By: Natixis Distribution Corporation,
its generalpartner

By: /s/ Coleen Downs Dinneen
    ------------------------------------
    Name: Coleen Downs Dinneen
    Title: Senior Vice President,
    General Counsel, Secretary and Clerk

GATEWAY INVESTMENT ADVISERS, LLC

By: /s/ J. Patrick Rogers
    ------------------------------------
    Name: J. Patrick Rogers
    Title: President

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