EXHIBIT 4.b.5


                   INVESTMENT SUB-ADVISORY AGREEMENT
                                BETWEEN
                   RETIREMENT SYSTEM INVESTORS INC.
                                  AND
                   NORTHERN TRUST INVESTMENTS, N.A.







                  THIS AGREEMENT effective as of October 1, 2004 is entered into
between Retirement System Investors Inc., a Delaware Corporation (the
"Adviser"), and Northern Trust Investments, N.A. (the "Manager").


                              W I T N E S S E T H:
                              - - - - - - - - - -


                  WHEREAS, RSI Retirement Trust ("the Trust"), a trust organized
and existing pursuant to an Agreement and Declaration of Trust made as of
October 22, 1940, as amended from time to time ("Agreement and Declaration of
Trust"), which provides benefits for the employees (and their beneficiaries) of
savings institutions, related organizations, other corporate entities which have
established plans of participation and individual retirement accounts
("Unitholders") in the Trust; and

                  WHEREAS, the Trust is an investment company registered under
the Investment Company Act of 1940, as amended (the "Act"); and

                  WHEREAS, the Trustees of the Trust ("Trustees") are vested
with authority for the management and control of the assets of the Trust in
accordance with the provisions of the Agreement and Declaration of Trust and in
furtherance of such authority are vested with the power to designate an
investment manager or managers to manage (including the power to acquire and
dispose of) the assets of any of the Investment Funds (as defined in the
Agreement and Declaration of Trust) of the Trust; and

                  WHEREAS, the Trust and the Adviser have entered into an
Investment Management Agreement dated June 4, 2004, pursuant to which the
Adviser may designate Sub-Advisers to perform certain investment advisory
functions under the supervision of the Adviser and the Trustees; and

                  WHEREAS, the Trust and the Manager have previously entered
into an Investment management Agreement dated as of September 15, 2003, under
which the Manager manages a portion of the assets of the Trust, serving as a
sub-adviser to the Adviser; and


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                  WHEREAS, the Adviser wishes to appoint the Manager to continue
to manage a portion of the assets of the Trust, to act in such a capacity in the
manner set forth in this Agreement, and the Manager is willing to act in such
capacity in accordance with the provisions of this Agreement;

                  NOW, THEREFORE, the Trust hereby agrees with the
Manager as follows:


                  1. Appointment of the Manager

                  A. The Adviser hereby designates, appoints, engages and
retains the Manager as investment manager of the assets comprising the
Investment Fund of the Trust referred to on Schedule A hereto ("Investment
Fund"). The portion thereof to be managed by the Manager ("Account") shall be
designated by the Adviser.

                  B. The Adviser represents and warrants that it has the
authority to enter into this Investment Management Agreement with the Manager
pursuant to a vote of Trust unitholders, cast at a meeting called for the
purpose of voting on such approval, of a majority of the Trustees of the Trust
who are not parties to this Agreement or interested persons of any such party
and the provisions of Rule 15a-4 under the Act.

                  C. The Manager hereby accepts appointment to manage the assets
of the Account.

                  D. The term of this Agreement shall commence on the effective
date hereof and shall continue thereafter for a period of one year from the date
hereof and thereafter from year to year provided that such continuance is
approved annually in the manner required by the Act. The Adviser agrees to use
its best efforts to obtain the approval referenced in the preceding sentence.

                  E. The Manager and Adviser understand that the Investment Fund
is being managed in a "manager-of-managers" style, and understand and agree
that, pursuant to that management style, the Adviser will, among other things:
(1) continually evaluate the performance of the Manager and any other
subadvisers to the Investment Fund through quantitative and qualitative analysis
and consultations with the Manager and other subadvisers, if any, (2)
periodically make recommendations to the Trustees as to whether the contract
with one or more subadvisers should be renewed, modified, or terminated, and (3)
periodically report to the Trustees regarding the results of its evaluation and
monitoring functions. The Manager acknowledges that its services may be modified
or terminated pursuant to this process.

                  2. Assets of the Account

                  The Adviser shall certify or cause to be certified to the
Manager the assets comprising the Account as of the commencement of the term of
this Agreement. The Adviser may add to the Account assets acceptable to the
Manager or withdraw assets from the Account at any time or from time to time by
notification to the Manager. The Account shall consist of the assets certified
to the Manager as aforesaid, or any assets into which the same may be converted
from


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time to time, together with any income therefrom or any other increment thereon
and assets added as aforesaid, less assets withdrawn as aforesaid.

                  3. Investment Powers

                  A. Subject to the provisions of paragraph B. of this Section
3, the Manager shall have exclusive authority and discretion, subject to and
consistent with the investment objectives and policies of the Investment Fund as
set forth in the current Prospectus of the Trust delivered to the Manager
("Prospectus") and as specified in writing from time to time by the Trustees or
the Adviser and accepted by the Manager, to manage (including the power to
acquire and dispose of) the assets of the Account, and, without limiting the
generality of the foregoing, to direct the Trustees in the exercise of the
powers relating to the Account which are specified in the Agreement and
Declaration of Trust as subject to such direction and as specified in writing
from time to time by the Trust and accepted by the Manager..

                  B. Notwithstanding the provisions of paragraph A. of this
Section 3, it is understood and agreed that an investment manager other than the
Manager may lend securities from the Account and may invest assets of the
Account on a temporary basis pending permanent investment or distribution, and
the Manager shall have no liability or responsibility with respect to the
exercise of such authority by such other investment manager; provided, however,
that the Manager shall coordinate the exercise of its authority hereunder which
may be affected by the exercise of such authority by the other investment
manager in such manner appropriate to the exercise of its authority as shall be
agreed upon by the Manager and such other investment manager. The Adviser will
advise the Manager of any arrangement with respect to any proposed lending of
securities from the Account.

                  C. The Manager shall consult with the Adviser or Trustees at
such times as the Adviser or the Trustees shall reasonably request with respect
to the overall investment policy of the Account, and with the instructions and
directions of the Adviser and of the Trustees, co-operate with the Adviser's (or
its designee's) personnel responsible for monitoring the Investment Fund's
compliance with and will conform to and comply with, the requirements of the
Act, the Internal Revenue Code of 1986, as amended, and all other applicable
federal and state laws and regulations including, among other things, the
preparation and filing of such reports as are, or may in the future be, required
by the Securities and Exchange Commission (the "Commission").

                  4. Standard of Care

                  A. The Manager shall invest the assets of the Account in the
manner provided herein and shall have no duty or responsibility with respect to
the diversification of the assets of the Trust, except with respect to the
diversification of the assets of the Account as contemplated by the Prospectus.

                  B. The Manager will be under no liability or obligation to
anyone with respect to any failure on the part of the Trust or any other
investment manager to perform any of their obligations under any agreement
affecting the Account or under the terms of this Agreement or for any error or
omission whatsoever on the part of the Trust, the Adviser, or any other
investment manager.


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                  C. The Manager shall not be liable for the making retention or
sale of any investment or reinvestment made by it as herein provided, nor for
any loss to or diminution of the value of the property of the Account; provided,
however, that the Manager has acted in the premises with the care, skill,
prudence, and diligence under the circumstances then prevailing that a prudent
man acting in like capacity and familiar with such matters would use in the
conduct of any enterprise of a like character and with like aims; provided,
further, however, that nothing in this Agreement shall protect the Manager
against any liability to the Adviser, the Trust or Unitholders to which the
Manager would otherwise be subject by reason of willful misfeasance, bad faith
or negligence in the performance of its duties hereunder or by reason of its
reckless disregard of its obligations and duties hereunder. Nothing herein shall
be construed to waive any liability that the Manager has under federal or state
securities laws or any other applicable laws which cannot be waived.

                  D. The Manager may not consult with any other manager or
sub-adviser of the Investment Fund, including any other manager or sub-adviser
that is a principal underwriter or an affiliated person of a principal
underwriter, concerning transactions of the Investment Fund in securities or
other assets. Notwithstanding the terms of the this paragraph 4.D., the Manager
may consult at all times with the Adviser engaged by the Trust.


                  5. General Provisions

                  A. Compensation for the services of the Manager will be as set
forth in Schedule A hereto.

                  B. With respect to securities in the Account, the Manager
shall purchase such securities from or through and sell such securities to or
through such persons, brokers or dealers as the Manager shall deem appropriate
to carry out the policy with respect to brokerage as set forth in the Prospectus
or as the Manager may direct from time to time. In providing the Account with
investment supervision, it is recognized that the Manager will give primary
consideration to securing the most favorable price and efficient execution. The
Manager shall have discretion to effect investment transactions for the
Investment Fund through broker-dealers (including, to the extent legally
permissible, broker-dealers affiliated with the Manager) qualified to obtain
best execution of such transactions who provide brokerage and/or research
services, as such services are defined in Section 28(e) of the Exchange Act of
1934, as amended (the "Exchange Act"). The Manager shall not be responsible for
any acts or omissions by any such broker or brokers, or any third party not
owned by the Manager, provided that the Manager is not negligent in the
selection of such broker or brokers, or third parties. The Manager is hereby
authorized to combine orders on behalf of the Account with orders on behalf of
other clients of the Manager. It is understood that it is desirable for the
Trust that the Manager have access to supplemental research and security and
economic analysis and statistical services and information with respect to the
availability of securities or purchasers or sellers of securities provided by
brokers and of use to the Trust although such access may require the allocation
of brokerage business to brokers who execute transactions at a higher cost to
the Trust than other brokers who provide only execution of portfolio
transactions. Therefore, the Manager is authorized to place orders for the
purchase and sale of securities with such brokers, subject to review by the
Trust from time to time with respect to the


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extent and continuation of this practice. It is understood that the services
provided by such brokers may be useful to the Manager in connection with its
services to other clients.

                  C. This Agreement shall automatically terminate in the event
of its "assignment" (as that term is defined in the Act) or upon termination of
the Investment Management Agreement between the Trust and the Adviser. The
Manager agrees that it will promptly notify the Trust and the Adviser of the
occurrence or anticipated occurrence of any event that would result in the
assignment of this Agreement, including, but not limited to, a change or
anticipated change in control (as defined in the Act) of the Manager; provided
that the Manager need not provide notice of such an anticipated event before the
anticipated event is a matter of public record.

                  D. This Agreement may be terminated, without the payment of
any penalty, by either party hereto on not more than sixty (60) days' nor less
than thirty (30) days' written notice delivered or mailed by registered mail,
postage prepaid, to the other party; any such termination on behalf of the Trust
to be pursuant to a vote of the Trustees or by a vote of a majority of the
outstanding voting securities (as defined in the Act) of the Investment Fund.

                  E. The Manager shall maintain all books and records with
respect to the Investment Fund's portfolio transactions effected by it as
required by subparagraphs (b)(5), (6), (7), (9), (10) and (11) and paragraph (f)
of Rule 31a-1 under the Act, and shall furnish to the Investment Fund's Board of
Trustees such periodic and special reports as the Trustees may reasonably
request. The Manager shall make reasonably available its employees and officers
for consultation with the Trustees or officers or employees of the Adviser with
respect to any matter discussed herein, including, without limitation, the
valuation of the Investment Fund's securities.

                  F. The Manager or an affiliate shall provide the Investment
Fund's custodian on each business day with information relating to all
transactions concerning the portion of the Investment Fund's assets it manages,
and shall provide the Adviser with such information upon request of the Adviser.

                  G. The Manager shall keep the Investment Fund's books and
records required to be maintained by the Manager pursuant to this Agreement and
shall timely furnish to the Adviser all information relating to the Manager's
services hereunder needed by the Adviser to keep the other books and records of
the Investment Fund required by Rule 31a-1 under the Act or any successor
regulation. The Manager agrees that all records which it maintains for the
Investment Fund are the property of the Investment Fund, and the Manager will
surrender promptly to the Investment Fund any of such records upon the
Investment Fund's request; provided, however, that the Manager may retain a copy
of such records. The Manager further agrees to preserve for the periods
prescribed by Rule 31a-2 of the Commission under the Act or any successor
regulation any such records as are required to be maintained by it pursuant to
this Agreement.

                  H. The Manager may rely on the authenticity, truth and
accuracy of, and will be fully protected in acting upon:


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                  (a)   Any notice, direction, certification,
                        approval or other writing of the Adviser,
                        if evidenced by an instrument signed by the
                        President, a Vice President, the Treasurer
                        or the Assistant Treasurer of the Adviser;

                  (b)   Any copy of a resolution of the Trustees,
                        if certified by the Secretary of the Trust;

                  (c)   Any notification or information provided by
                        the custodian of the assets in the Account,
                        if evidenced by an instrument signed by an
                        officer of the custodian; or

                  (d)   Any oral notice or instruction reasonably
                        believed to be genuine and to be given by
                        the Adviser or the Trustees or its
                        authorized delegate or by the custodian or
                        any other investment manager.

                  I. The Manager may rely on, and will be fully protected with
respect to any action taken or omitted in reliance on, any information,
statement or certificate delivered to the Manager by the Adviser or Trustees
with respect to any matter concerning the Trust and the operation and
administration of the Account. The Manager is expressly authorized to consult
with the Adviser with respect to any matters arising in the administration of
the Account and to act on the advice of the Adviser, provided nothing herein
shall limit the full responsibility of the Manager for the management of the
assets of the Account as provided herein.

                  J. Communications from the Manager to the Adviser shall be
addressed to:

                          Retirement System Investors Inc.
                          150 East 42nd Street - 27th Floor
                          New York, New York 10017-5633
                          Attn.: Stephen P. Pollak
                                 Executive Vice President, Counsel and Secretary

Communications to the Manager from the Adviser shall be addressed to
the address set forth in Schedule A hereto. In the event of a change
of address, communications shall be addressed to such new address as
designated in a written notice from the Adviser, the Trustees or the
Manager, as the case may be. All communications addressed in the above
manner and by ordinary mail, overnight courier, registered mail or
delivered by hand shall be sufficient under this Agreement.

                  K. Unless the Adviser instructs the Manager otherwise in
writing, the Manager will vote proxies for securities held in the Account in
accordance with the Manager's written policies for proxy voting. The Adviser
agrees to instruct the custodian to forward to the Manager copies of all proxies
and shareholder communications relating to securities held in the Account. The
Adviser agrees that the Manager will not be liable for failing to vote any
proxies where it has not received such proxies or related shareholder
communications on a timely basis. The Manager will not be responsible for taking
any action or rendering any advice with respect to any legal proceedings or
bankruptcies involving the issuers of securities held in the Account.


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                  L. In connection with its duties under this Agreement, the
Manager agrees to maintain adequate compliance procedures to ensure its
compliance with the Act, the Investment Advisers Act of 1940, and other
applicable federal and state laws and regulations.

                  M. The Adviser acknowledges (i) receipt of the written
disclosure statement required by Rule 204-3 of the Investment Advisers Act of
1940 at least 48 hours before execution of this Agreement; (ii) that services
provided hereunder by Manager shall not be deemed exclusive and that Manager
shall be free to render similar services to others; and (iii) that Manager may
give advice and take action in the performance of duties to others which may
differ from the advice given, or the timing and nature of the action taken, with
respect to the Trust's Account.

                  N. All agreements hereunder will be governed by the laws of
the State of New York, without reference to such State's conflict of law rules.

                  O. No term or provision of this Agreement may be amended,
modified or waived without the affirmative vote or action by the written
agreement of the Trust and the Manager and in accordance with the Act.

                  P. Without the prior express consent of the Manager, the
Adviser agrees that it will not use the name, logo, insignia, or other
identifying mark of the Manager or any person controlling, controlled by or
under common control with the Manager (a "Manager Affiliate") or describe the
Manager any Manager Affiliate in any manner or in any materials, including
registration statements and marketing and sales materials, without providing
such materials to the Manager within a reasonable time prior to such proposed
use, and providing the Manager reasonable time to approve, modify or reject such
materials, except that sales or marketing materials containing the same text
referring to the Manager as that used in previously approved materials may be
used by the Trust without prior submission to the Manager. The Manager agrees
that it shall not unreasonably withhold approval of any such materials.

                  Q. The parties acknowledge and agree that (a) the Manager is
not the sponsor, administrator or distributor of, and does not control, the
Trust, the Adviser, Investment Fund or Account, (b) no director, officer or
employee of the Manager or of any Manager Affiliate serves as a trustee, officer
or employee of the Trust, the Adviser, Investment Fund or Account, and (c) the
Manager's responsibilities hereunder relate solely to the day-to-day management
of the assets in the Account and the Manager has no responsibility for any other
aspect of the operations or administration of the Trust, the Adviser, Investment
Fund or Account. Without limiting the foregoing, the Manger shall have no
responsibility in determining the fair value of any asset held by the Trust,
Investment Fund or Account, except that the Manager shall provide, as requested,
reasonable assistance to the Trust, the Adviser, or any other investment adviser
engaged by the Trust to act as adviser pursuant to Section 1.E above, in making
such a determination as to any asset held by the Account.

                  R. The Adviser agrees to indemnify and hold harmless the
Manager and any Manager Affiliate, and any shareholder, partner, director,
officer and employee of any of the foregoing (each an "Indemnified Manager
Party"), against any loss, claim, settlement, damage, charge, liability or
expense, including, without limitation, reasonable attorneys' and accountants'
fees ("Losses"), to which such persons may become subject, insofar as such
Losses arise out of or


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are based upon (a) any inaccuracy or omission in any prospectus, registration
statement, annual or other periodic report or proxy statement of the Trust or
any advertising, marketing, shareholder communication, or promotional material
generated, by the Adviser or the Trust unless such inaccuracy or omission was
caused by an Indemnified Manager Party, (b) any violation of any law, rule or
regulation relating to the registration or qualification of shares of the Trust,
(c) any breach by the Adviser of any representation, warranty or agreement
contained in this Agreement or (d) the services provided by the Manager to the
Adviser hereunder or the operation of the Trust except to the extent such Losses
result from an Indemnified Manager Party's willful misfeasance, bad faith, or
negligence.








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                  IN WITNESS WHEREOF, the Adviser and the Manager have
executed this Agreement, effective as of the date of this Agreement
first set forth above.



                                      NORTHERN TRUST INVESTMENTS, N.A.

                                      By:
                                         ---------------------------------------

                                      Title:
                                            ------------------------------------

                                      RETIREMENT SYSTEM INVESTORS INC.

                                      By:
                                         ---------------------------------------

                                      Title: Executive Vice President, Counsel
                                             and Secretary


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<PAGE>


                                   SCHEDULE A


                        RETIREMENT SYSTEM INVESTORS INC.
                        INVESTMENT SUB-ADVISORY AGREEMENT


Name of Manager:     Northern Trust Investments, N.A.
Address:             50 South LaSalle Street
                     Chicago, Illinois 60675



Attention:           Mr. Michael Lucas


Investment Fund:     Core Equity Fund

Compensation Terms:

Terms used herein shall have the meaning used in the Investment Management
Agreement between the Adviser and the Manager ("Agreement"). The Adviser agrees
to pay to the Manager, as full compensation and reimbursement for the services
to be rendered pursuant to the Agreement and any expenses incurred in connection
therewith, a fee at the end of each fiscal quarter of the Trust, computed by
applying the following rate the Account:

          Effective October 1, 2004, 0.16% of the first $25 million of
          assets, 0.10% of the next $25 million of assets, 0.06% of
          the next $50 million of assets, and 0.04% of assets in
          excess of $100 million.


Billing is done for each quarter on the basis of services performed during that
particular quarter. The quarterly fee is calculated on the basis of the average
of the asset value as of the last day of each month of each calendar quarter,
equal to one-fourth of the annual rate.

If the Agreement commences on a date other than on the beginning of any such
quarterly period, or terminates on a date other than the end of any such
quarterly period, the fee payable hereunder shall be proportionately reduced
according to the number of days during such period services were rendered by the
Manager.


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IN WITNESS WHEREOF, the parties to the Agreement, effective as of October 1,
2004, have executed this Schedule A, effective as of the same dates.


                                      NORTHERN TRUST INVESTMENTS, N.A.

                                      By:
                                         ---------------------------------------

                                      Title:
                                            ------------------------------------

                                      RETIREMENT SYSTEM INVESTORS INC.

                                      By:
                                         ---------------------------------------

                                      Title:Executive Vice President, Counsel
                                            and Secretary


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