Exhibit (a)(1)

                            STATE STREET MASTER FUNDS
                   STATE STREET INSTITUTIONAL INVESTMENT TRUST

                   CODE OF ETHICS FOR PRINCIPAL EXECUTIVE AND
                            SENIOR FINANCIAL OFFICERS

I.       COVERED OFFICERS/PURPOSE OF THE CODE

         This Code of Ethics (the "Code") shall apply to the State Street Master
Funds' and State Street Institutional Investment Trust's (each a "Trust")
Principal Executive Officer, Principal Financial Officer, Controller, Principal
Accounting Officer and persons performing similar functions (the "Covered
Officers," each of whom is named in Exhibit A attached hereto) for the purpose
of promoting:

- -        honest and ethical conduct, including the ethical handling of actual or
         apparent conflicts of interest between personal and professional
         relationships;

- -        full, fair, accurate, timely and understandable disclosure in reports
         and documents that the Trust files with, or submits to, the Securities
         and Exchange Commission ("SEC") and in other public communications made
         by the Trust;

- -        compliance with applicable laws and governmental rules and regulations;

- -        the prompt internal reporting of violations of the Code to an
         appropriate person or persons identified in the Code; and

- -        accountability for adherence to the Code.

Each Covered Officer should adhere to a high standard of business ethics and
should be sensitive to situations that may give rise to actual as well as
apparent conflicts of interest.

II.      COVERED OFFICERS SHOULD HANDLE ETHICALLY ACTUAL AND APPARENT CONFLICTS
         OF INTEREST

         OVERVIEW. A "conflict of interest" occurs when a Covered Officer's
private interest interferes with the interests of, or his service to, the Trust.
For example, a conflict of interest would arise if a Covered Officer, or a
member of his family, receives improper personal benefits as a result of his
position with the Trust. Covered Officers must avoid conduct that conflicts, or
appears to conflict, with their duties to the Trust. All Covered Officers should
conduct themselves such that a reasonable observer would have no grounds for
belief that a conflict of interest exists. Covered Officers are not permitted to
self-deal or otherwise to use their positions with the Trust to further their
own or any other related person's business opportunities.



         This Code does not, and is not intended to, repeat or replace the
programs and procedures or codes of ethics of the Trust's investment adviser or
distributor.

         Although typically not presenting an opportunity for improper personal
benefit, conflicts may arise from, or as a result of, the contractual
relationship between the Trust and its service providers, including investment
adviser, of which the Covered Officers may be officers or employees. As a
result, this Code recognizes that the Covered Officers will, in the normal
course of their duties (whether formally for the Trust, the investment adviser,
or other service providers), be involved in establishing policies and
implementing decisions that will have different effects on the service providers
and the Trust. The participation of the Covered Officers in such activities is
inherent in the contractual relationship between the Trust and its service
providers and is consistent with the performance by the Covered Officers of
their duties as officers of the Trust. Thus, if performed in conformity with the
provisions of the Investment Company Act of 1940, as amended ("Investment
Company Act") and the Investment Advisers Act of 1940, as amended ("Investment
Advisers Act"), such activities will be deemed to have been handled ethically.
In addition, it is recognized by the Trust's Boards of Trustees (the "Board")
that the Covered Officers may also be officers or employees of one or more other
investment companies covered by this or other codes.

         The following list provides examples of conflicts of interest under the
Code, but Covered Officers should keep in mind that these examples are not
exhaustive. The overarching principle is that the personal interest of a Covered
Officer should not be placed improperly before the interest of the Trust.

                                     * * * *

Each Covered Officer must not:

- -        use his or her personal influence or personal relationship improperly
         to influence investment decisions or financial reporting by the Trust
         whereby the Covered Officer would benefit personally to the detriment
         of the Trust;

- -        cause the Trust to take action, or fail to take action, for the
         individual personal benefit of the Covered Officer rather than the
         benefit of the Trust; or

- -        retaliate against any other Covered Officer or any employee of the
         Trust or their affiliated persons for reports of potential violations
         by the Trust of applicable rules and regulations that are made in good
         faith.

         Each Covered Officer must discuss certain material conflict of interest
situations with the Trust's Audit Committee. Examples of such situations
include:

- -        service as a director, trustee, general partner, or officer of any
         unaffiliated business organization. This rule does not apply to
         charitable, civic, religious, public, political, or social
         organizations, the activities of which do not conflict with the
         interests of the Trust;

- -        the receipt of any non-nominal gifts;



- -        the receipt of any entertainment from any company with which the Trust
         has current or prospective business dealings unless such entertainment
         is business-related, reasonable in cost, appropriate as to time and
         place, and not so frequent as raise any question of impropriety;

- -        any ownership interest in, or any consulting or employment relationship
         with, any of the Trust's service providers, other than its investment
         adviser, principal underwriter, administrator, transfer agent,
         custodian or any affiliated person thereof; and

- -        a direct or indirect financial interest in commissions, transaction
         charges or spreads paid by the Trust for effecting portfolio
         transactions or for selling or redeeming shares other than an interest
         arising from the Covered Officer's employment, such as compensation or
         equity ownership.

III.     DISCLOSURE AND COMPLIANCE

- -        Each Covered Officer should familiarize himself or herself with the
         disclosure requirements generally applicable to the Trusts.

- -        Each Covered Officer should not knowingly misrepresent, or cause others
         to misrepresent, facts about the Trust to others, whether within or
         outside the Trust, including to the Trust's Board, Trust's Audit
         Committee and the Trust's independent auditors, and to governmental
         regulators and self-regulators and self-regulatory organizations.

- -        Each Covered Officer should, to the extent appropriate within his or
         her area of responsibility, consult with other officers and employees
         of the Trust and its service providers with the goal of promoting full,
         fair, accurate, timely and understandable disclosure in the reports and
         documents the Trust files with, or submits to, the SEC and in other
         public communications made by the Trust.

- -        It is the responsibility of each Covered Officer to promote and
         encourage professional integrity in all aspects of the Trusts'
         operations.

IV.      REPORTING AND ACCOUNTABILITY

         Each Covered Officer must:

- -        upon adoption of this Code (or thereafter as applicable, upon becoming
         a Covered Officer), sign and return a report in the form of Exhibit B
         to the Trust's compliance officer affirming that he or she has
         received, read, and understands the Code;

- -        annually sign and return a report in the form of Exhibit C to the
         Trust's compliance officer as an affirmation that he or she has
         complied with the requirements of the Code; and



- -        notify the Trust's Audit Committee promptly if he or she knows of any
         violation of this Code. Failure to do so is itself a violation of this
         Code.

         The Trust's Audit Committee is responsible for applying this Code to
specific situations in which questions are presented under it and has the
authority to interpret this Code in any particular situation including any
approvals or waivers sought by the Covered Persons.

         The Audit Committee will follow these procedures in investigating and
enforcing this Code:

- -        The Audit Committee will take all appropriate actions to investigate
         any potential violations reported to the Committee.

- -        If, after such investigation, the Audit Committee believes that no
         violation has occurred, the Audit Committee is not required to take any
         further action.

- -        Any matter that the Audit Committee believes is a violation of this
         Code will be reported to the full Board.

- -        If the Board concurs that a violation has occurred, it will notify the
         appropriate personnel of the applicable service provider and may
         dismiss the Covered Officer as an officer of the Trust.

- -        The Audit Committee will be responsible for granting waivers of
         provisions of this Code, as appropriate.

- -        Any changes to or waivers of this Code will, to the extent required, be
         disclosed as provided by SEC rules.

V.       OTHER POLICIES AND PROCEDURES

         This Code shall be the sole code of ethics adopted by the Trust for
purposes of Section 406 of the Sarbanes-Oxley Act and the rules and forms
applicable to registered investment companies thereunder. Insofar as other
policies or procedures of the Trust, the Trust's investment adviser, principal
underwriter, or other service providers govern or purport to govern the behavior
or activities of the Covered Officers who are subject to this Code, they are
superseded by this Code to the extend that they overlap or conflict with the
provisions of this Code. The Trust's, investment adviser's and principal
underwriter's codes of ethics under Rule 17j-1 under the Investment Company Act
and the investment adviser's more detailed policies and procedures are separate
requirements applying to the Covered Officers and others, and are not part of
this Code.



VI.      AMENDMENTS

         Any amendments to this Code, other than amendments to Exhibit A, must
  be approved or ratified by a majority vote of the Board, including a majority
  of independent Trustees.

VII.     CONFIDENTIALITY

         All reports and records prepared or maintained pursuant to this Code
  will be considered confidential and shall be maintained and protected
  accordingly. Except as otherwise required by law or this Code, such matters
  shall not be disclosed to anyone other than the Trust's Board or Audit
  Committee.

VIII.    INTERNAL USE

         The Code is intended solely for the internal use by the Trust and does
  not constitute an admission, by or on behalf of the Trust, as to any fact,
  circumstance, or legal conclusion.

  Date: September 18, 2003



EXHIBIT A

Persons Covered by this Code of Ethics:

Donald A. Gignac
President

Karen D. Gillogly
Treasurer



                                    EXHIBIT B

                           INITIAL CERTIFICATION FORM

         This is to certify that I have read and understand the Code of Ethics
for Principal Executive and Senior Financial Officers of State Street Master
Funds and State Street Institutional Investment Trust, dated September 18, 2003,
and that I recognize that I am subject to the provisions thereof and will comply
with the policy and procedures stated therein.

         Please sign your name here:_________________________________________

         Please print your name here:________________________________________

         Please date here:___________________________________________________



                                    EXHIBIT C

                            ANNUAL CERTIFICATION FORM

         This is to certify that I have read and understand the Code of Ethics
for Principal Executive and Senior Financial Officers of State Street Master
Funds and State Street Institutional Investment Trust, dated September 18, 2003,
(the "Code") and that I recognize that I am subject to the provisions thereof
and will comply with the policy and procedures stated therein.

         This is to further certify that I have complied with the requirements
of the Code during the period of _____________ through _____________.

         Please sign your name here:________________________________

         Please print your name here:_______________________________

         Please date here:__________________________________________