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                                                                   Exhibit 10.23


                              AMENDED AND RESTATED
                              EMPLOYMENT AGREEMENT

       AMENDED AND RESTATED EMPLOYMENT AGREEMENT (the "Agreement") made as of
this 16th day of May, 2000 by and among Robert D. Mancuso ("Employee"),
Investors Financial Services Corp., a Delaware corporation ("IFSC"), and
Investors Bank & Trust Company, a Massachusetts chartered trust company having
its principal place of business at 200 Clarendon Street, Boston, Massachusetts
(the "Company").

       WHEREAS, IFSC, the Company and the Employee are parties to an employment
agreement, dated as of October 11, 1995, as amended (the "Prior Agreement"), and
the parties thereto wish to enter into this Agreement in order to update the
Prior Agreement;

       NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, and in consideration of the mutual
covenants and obligations herein contained, the parties hereto agree as follows:

       1. POSITION AND RESPONSIBILITIES. During the term of this Agreement, the
Employee shall serve as Senior Vice President -Marketing and Client Management
of the Company and of IFSC. The Employee will have such responsibilities, duties
and authority as he has as of the date hereof in his positions as Senior Vice
President -Marketing and Client Management of the Company and of IFSC. The
Employee will have such other responsibilities, duties and authority as may from
time to time be assigned to him that are consistent and commensurate with his
status and positions at the Company and IFSC. The Employee shall at all times
report to, and only to, and his activities shall at all times be subject to the
direction and control of, the Chief Executive Officer of the Company, and the
Employee shall exercise such powers and comply with and perform, faithfully and
to the best of his ability, such directions and duties in relation to the
business and affairs of the Company, as may from time to time be vested in or
requested of him by the Chief Executive Officer of the Company. The Employee
agrees to devote substantially all of his business time, attention and services
to the diligent, faithful and competent discharge of such duties for the
successful operation of the Company's business. During the term hereof, the
Employee will not have any managerial or operations responsibility, other than
service on a board of directors, in any enterprise, firm, corporation, trust or
other business entity other than the Company and IFSC; provided, however, that
nothing herein shall prevent the ownership by the Employee of an equity interest
in any business entity, provided that such ownership does not involve any
managerial or operational responsibility other than serving on the board of
directors of a corporation. Any directorships of corporations other than the
Company and IFSC must be approved in writing by the Board of Directors of IFSC
(the "IFSC Board") in advance. At all times during the term of this Agreement,
the Employee's primary place of employment shall be within fifteen (15) miles of
Boston, Massachusetts.

       2. COMPENSATION: SALARY, COMMISSION, EQUITY PARTICIPATION AND OTHER
BENEFITS. During the term of this Agreement, the Company shall pay the Employee
the following compensation, including the following salary, commission and other
fringe and welfare benefits:

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       (A) SALARY. In consideration of the services to be rendered by the
Employee to the Company and IFSC, the Company will pay to the Employee an annual
base salary of $275,000 (the "Base Rate"). Such Base Rate shall be payable in
conformity with the Company's customary practices for executive compensation as
such practices shall be established or modified from time to time. The
Employee's Base Rate shall be evaluated annually by the IFSC Board or the
Compensation Committee thereof, and may be increased as appropriate, within
thirty (30) days of the end of each calendar year, but in no circumstances shall
the Base Rate be decreased below the Base Rate that was established for the most
recently concluded calendar year.

       (B) WELFARE AND FRINGE BENEFITS. The Employee will be entitled to
participate in the Company's welfare and fringe benefit plans, programs and
policies generally available to other senior executives of the Company, on the
same basis as such other senior executives. In addition, the Employee will be
entitled to four (4) weeks vacation during each calendar year, which shall
accrue if and to the extent unused. The Employee will be entitled to be
reimbursed for all of his business-related expenses, including but not limited
to telephone usage and business related travel expenses.

       (C) SALES INCENTIVE COMMISSION. For each twelve month period ending on
December 31 during the term of this Agreement, in addition to the amounts
payable under Section 2(A) above, the Employee shall receive a sales incentive
commission (the "Annual Commission"), with the amount of such commission to be
determined pursuant to such sales commission plan as may from time to time be
adopted by the Chief Executive Officer of the Company. The Annual Commission
shall be payable at such times as the Chief Executive Officer of the Company
shall establish, provided that the Employee continues to be employed by the
Company on each payment date.

       (D) EQUITY PARTICIPATION.

            (i) The Employee shall be entitled to participate annually in the
       1995 Stock Plan and any future equity compensation plan that is generally
       made available to other senior executives of the Company, in such amounts
       and on such terms as are determined appropriate thereunder commensurate
       with his position and performance, and in accordance with all of the
       terms and conditions of such plan.

            (ii) The Company agrees that with respect to all options and
       restricted shares to be granted by the Company, upon grant and during the
       term of such options and the vesting period of such restricted shares,
       the Company shall use its reasonable efforts to comply with the
       requirements of Rule 16b-3, promulgated pursuant to the Securities
       Exchange Act of 1934, as amended, as such rule shall be in effect from
       time to time, or with any successor provision ("Rule 16b-311") such that
       such options and restricted shares shall be afforded the benefits of Rule
       16b-3.

            (iii) The Company agrees that it shall use its best efforts to file
       and cause to become and remain effective a registration statement on Form
       S-8 (or a successor form) such that either the resale by the Employee of
       restricted shares granted to the Employee

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       by the Company or the grant of such shares and the purchase of shares by
       the Employee upon the exercise of the options to be granted to the
       Employee shall be registered under the; Securities Act of 1933, as
       amended, or any successor provision.

       (E) LIFE INSURANCE PREMIUM PAYMENTS AND TAX GROSS-UP. The Company shall
pay to the Employee the cost of premiums (such payments to be "grossed-up" to
account for the tax liability to the Employee on such payments) for a life
insurance policy for the benefit of the Trustees of an insurance trust
designated by the Employee or such other entity or individual as the Employee
shall so designate (the "Life Insurance Policy"). The amount of such policy
shall not exceed the amount of the termination for Good Reason severance payment
determined under Section 4(A) hereof. The Company shall provide reasonable
assistance to the Employee in obtaining the Life Insurance Policy.

       3. TERM. The term of this Agreement shall commence on the date first
above written and shall terminate on the earlier to occur of (i) three (3) years
from such date, or, if later, three (3) years from the date upon which the IFSC
Board last renewed the term as provided below; (ii) the Employee's death, or
upon written notice from the Company to the Employee, if the Employee is
permanently disabled, or (iii) the occurrence of any of the circumstances
described in Section 4 hereof. For the purposes of this Agreement, the Employee
shall be deemed to be permanently disabled if a physician, chosen by the
Company, and reasonably acceptable to the Employee or his legal representative,
determines in good faith that, as a result of a physical or mental condition
caused by injury, illness, disease or mental disorder, the Employee is unable to
perform his duties hereunder for any one hundred twenty (120) work days out of
any 365-day period or for ninety (90) consecutive days in any 365-day period.
Within thirty (30) days of December 31 of each calendar year, the IFSC Board
shall consider the extension of the term of this Agreement to three years from
such December 31. Each such extension shall be effective only when agreed to by
the Employee. In the event that the IFSC Board fails to extend the term of this
Agreement, the Employee may terminate this Agreement for "Good Reason," in
accordance with Section 4(A) hereof, notwithstanding any other term hereof.

       4. TERMINATION. The Employee's employment under this Agreement, and this
Agreement, subject to Section 16 hereof, may be terminated as follows:

       (A) BY THE EMPLOYEE WITH OR WITHOUT GOOD REASON. The Employee may
terminate his employment, with or without Good Reason (as defined below), at any
time upon at least sixty (60) days' advance written notice to the Company. In
the event of a family emergency, including but not limited to the death or
incapacity of an immediate family member, or upon other circumstances deemed
sufficient by a majority of the IFSC Board, the Employee may terminate his
employment upon fifteen (15) days' advance written notice to the Company. In the
event of termination at the Employee's option without Good Reason, the Employee
shall be entitled to no severance or other termination benefits after the
expiration of the sixty-day period referred to above, except as otherwise
required by law. In the event the Employee terminates his employment for Good
Reason, the Company agrees to pay the Employee, in a lump sum within fifteen
(15) days of the Employee's last day of employment with the Company, a severance
payment equal to the product of (i) the greater of (x) the remaining number of
months in the term


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of this Agreement and (y) twenty-four months (the "Severance Period"), divided
by twelve, multiplied by (ii) the sum of the Employee's Base Rate immediately
prior to such termination and the Recent Annual Commission (as defined below).
In addition, during the Severance Period, the Company shall continue to provide
the Employee and his eligible dependents (to the extent applicable) with group
health benefits and life and disability insurance on the same terms and
conditions applicable to active senior executives of the Company, including
cost-sharing (hereinafter the "Welfare Benefits"), provided, that if the Welfare
Benefits cannot be provided to inactive employees under the terms of the
applicable plans or applicable law, the Company shall provide the Employee with,
or pay the Employee for the cost of obtaining, substitute benefits that are no
less favorable in the aggregate than the Welfare Benefits as in effect
immediately prior to the Employee's termination. Notwithstanding the foregoing,
the Company's responsibility for the cost of the Welfare Benefits shall not
exceed twice the cost it paid for such coverage immediately prior to the
Employee's termination. As used in this Agreement, "Recent Annual Commission"
shall mean the highest Annual Commission paid or payable to the Employee
(including any deferred amounts) with respect to any of the three full calendar
years ending immediately prior to the Employee's termination of employment.

            As used in this Agreement, a "Good Reason" shall mean any of the
       following:

            (i) a material change by the Company or IFSC in the Employee's
       authority, functions, duties or responsibilities as Senior Vice President
       -Marketing and Client Management of the Company and IFSC (including,
       without limitation, material changes in the control or structure of the
       Company or IFSC) which would cause the Employee's position with the
       Company or IFSC to become of less responsibility, importance or scope
       than the Employee's position as of the date of this Agreement, provided
       that such material change is not in connection with a termination of the
       Employee's employment hereunder for Cause in accordance with Section 4B;

            (ii) a failure by the Company to renew this Agreement as provided in
       Section 3 hereof, provided that such nonrenewal is not in connection with
       a termination of the Employee's employment hereunder for Cause in
       accordance with Section 4B; or

            (iii) a failure by the Company to comply in a material respect with
       any material provision of this Agreement or any other agreement between
       the parties, which has not been cured within fifteen (15) days after
       notice of such noncompliance has been given by the Employee to the
       Company.

       (B) AT THE ELECTION OF THE COMPANY FOR CAUSE. The Company may,
immediately and unilaterally, terminate the Employee's employment hereunder for
Cause at any time during the term of this Agreement. Termination of the
Employee's employment by the Company shall constitute a termination for Cause
under this Agreement if such termination is for one or more of the following
reasons, as found by the IFSC Board by a resolution duly adopted in good faith
by a majority of its members after notice to the Employee and an opportunity to
be heard before the IFSC Board with counsel. As used herein, "Cause" shall mean:


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            (i) the continued failure or continued refusal of the Employee to
       render services to the Company or IFSC in accordance with his obligations
       under this Agreement or a reasonable determination by a majority of the
       IFSC Board that the Employee has performed inadequately the duties of his
       employment, in each case continuing for fifteen (15) days after the
       Employee's receipt of written notice specifying the alleged failure,
       refusal or performance inadequacy;

            (ii) gross negligence, dishonesty, breach of fiduciary duty or
       material breach of the material terms of this Agreement or the other
       agreements executed in connection herewith;

            (iii) the commission by the Employee of an act of fraud,
       embezzlement or deliberate disregard of the rules or policies of the
       Company or IFSC or the commission by the Employee of any other action
       with the intent to injure materially the Company or IFSC;

            (iv) the conviction by the Employee of a felony, either in
       connection with the performance of his obligations hereunder or that will
       materially and adversely affect the Employee's ability to perform his
       obligations hereunder; or

            (v) the commission of an act which constitutes unfair competition
       with the Company or which induces any customer of the Company to breach a
       contract with the Company.

       In the event of a termination for Cause pursuant to the provisions of
clauses (ii) through (v) above, inclusive, the Employee shall not be entitled to
severance or other termination benefits, except as required by law. In the event
of a termination for Cause pursuant to the provisions of clause (i) above, the
Company, notwithstanding the remaining term of this Agreement, agrees to (x) pay
the Employee a lump-sum severance payment equal to nine (9) months' salary at
the Employee's Base Rate, within fifteen (15) days of the Employee's last day of
employment by the Company and (y) provide continuing group health benefits
during the nine (9) month severance period to the Employee and his eligible
dependents on the same basis and terms and conditions, including cost-sharing,
as provided to other active senior executives of the Company during such period.

       (C) AT THE ELECTION OF THE COMPANY FOR REASONS OTHER THAN FOR CAUSE. The
Company may, immediately and unilaterally, terminate the Employee's employment
hereunder and this Agreement at any time during the term of this Agreement
without Cause by giving sixty (60) days' advance written notice to the Employee
of the Company's election to terminate. During such sixty-day period, the
Employee will be available on a full-time basis for the benefit of the Company
to assist the Company in making the transition to a new, successor officer of
the Company. In the event the Company exercises its right to terminate the
Employee under this Section 4(C), the Company agrees to pay the Employee, in a
lump sum within fifteen (15) days of the Employee's last day of employment with
the Company, a severance payment equal to the amount determined under Section
4(A) hereof and to provide the Welfare Benefits during the


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Severance Period, in each case as if the Employee had terminated employment for
Good Reason under Section 4(A) hereof.

       (D) TERMINATION DUE TO DEATH OR DISABILITY. In the event this Agreement
shall terminate due to the Employee's death or upon written notice from the
Company to the Employee if the Employee is permanently disabled, the Company
shall pay the Employee or his legal representatives an amount equal to the
amount payable under Section 4(C) as if the Employee had been terminated other
than for Cause, reduced by any amount payable to an insurance trust or such
other designated individual or entity under the Life Insurance Policy, if any,
in the case of the Employee's death, or under disability insurance provided by
the Company, in the case of the Employee's termination due to his permanent
disability. In addition, upon a termination of the Employee due to his permanent
disability, the Company shall continue to provide the Welfare Benefits during
the Severance Period, as if the Employee's employment had been terminated other
than for Cause under Section 4(C). The provisions of this Section 4(D) shall
survive the termination of this Agreement by reason of the death or permanent
disability of the Employee.

       5. NONCOMPETITION AND CONFIDENTIALITY. In connection with his employment
by the Company, the Employee has previously executed the Noncompetition and
Confidentiality Agreement attached hereto as EXHIBIT A, the terms and conditions
of which are incorporated herein by reference. The Noncompetition and
Confidentiality Agreement shall survive the termination of this Agreement and
shall remain in full force and effect for so long as is provided by its own
terms and as is permitted by law.

       6. CONSENT AND WAIVER BY THIRD PARTIES. The Employee hereby represents
and warrants that he has obtained all waivers and/or consents from third parties
which are necessary to enable him to enjoy employment with the Company on the
terms and conditions set forth herein and to execute and perform this Agreement
without being in conflict with any other agreement, obligation or understanding
with any such third party. The Employee represents that he is not bound by any
agreement or any other existing or previous business relationship, which
conflicts with, or may conflict with, the performance of his obligations
hereunder or prevent the full performance of his duties and obligations
hereunder.

       7. GOVERNING LAW. This Agreement, the employment relationship
contemplated herein and any claim arising from such relationship, whether or not
arising under this Agreement, shall be governed by and construed in accordance
with the internal law of the Commonwealth of Massachusetts and this Agreement
shall be deemed to be performable in Massachusetts.

       8. SEVERABILITY. In case any one or more of the provisions contained in
the Agreement or the other agreements executed in connection with the
transactions contemplated hereby for any reason shall be held to be invalid,
illegal or unenforceable in any respect, such invalidity, illegality or
unenforceability shall not affect any other provision of this Agreement or such
other agreements, but this Agreement or such other agreements, as the case may
be, shall be construed and reformed to the maximum extent permitted by law.


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       9. WAIVERS AND MODIFICATIONS. This Agreement may be modified, and the
rights, remedies and obligations contained in any provision hereof may be
waived, only in accordance with this Section 9. No waiver by either party of any
breach by the other or any provision hereof shall be deemed to be a waiver of
any later or other breach thereof or as a waiver of any other provision of this
Agreement. This Agreement sets forth all of the terms of the understandings
between the parties with reference to the subject matter set forth herein on or
after the date hereof and may not be waived, changed, discharged or terminated
orally or by any course of dealing between the parties, but only by an
instrument in writing signed by the party against whom any waiver, change,
discharge or termination is sought. No modification or waiver by the Company
shall be effective without the consent of at least a majority of the members of
the IFSC Board (excluding the Employee) then in office at the time of such
modification or waiver.

       10. ASSIGNMENT. The Employee acknowledges that the services to be
rendered by him hereunder are unique and personal in nature. Accordingly, the
Employee may not assign any of his rights or delegate any of his duties or
obligations under this Agreement, provided, however, that this Agreement shall
inure to the benefit of Employee's heirs, executors, administrators, personal
and legal representatives, distributees, devisees, legatees and successors. The
rights and obligations of the Company and IFSC under this Agreement shall inure
to the benefit of, and shall be binding upon, the successors and assigns of the
Company and IFSC, respectively. The Company and IFSC agree that a successor in
interest by merger, operation of law, consolidation, assignment, purchase or
otherwise of a controlling interest in the business of the Company or IFSC will
be informed prior to such event of the existence of this Agreement. The Company
and IFSC will require any successor (whether direct or indirect, by purchase,
merger, operation of law, consolidation, assignment or otherwise of a
controlling interest in the business, stock or other assets of the Company or
IFSC) to assume expressly and agree to perform this Agreement. As used in this
Agreement, "the Company" and "IFSC" shall mean the Company and IFSC as
hereinbefore defined and any successors as aforesaid.

       11. ACKNOWLEDGMENTS. The Employee hereby acknowledges and recognizes that
the enforcement of any of the provisions in this Agreement and the
Noncompetition and Confidentiality Agreement incorporated herein may potentially
interfere with the Employee's ability to pursue a proper livelihood. The
Employee represents that he is knowledgeable about the business of the Company.
The Employee recognizes and agrees that the enforcement of the Noncompetition
and Confidentiality Agreement is intended to ensure the preservation, protection
and continuity of the business trade secrets and goodwill of the Company. The
Employee agrees that, due to the proprietary nature of the Company's business,
the restrictions set forth in the Noncompetition and Confidentiality Agreement
are reasonable as to time and scope. The foregoing shall not prohibit the
Employee from employment with any company by which the Employee has been
employed in the past so long as his activities with any such company do not
otherwise constitute a breach of the Noncompetition and Confidentiality
Agreement.

       12. ENTIRE AGREEMENT. This Agreement, and the Noncompetition and
Confidentiality Agreement and any other plans or agreements referenced herein,
constitute the entire understanding of the parties relating to the subject
matter hereof and, except as provided herein, supersede and cancel all
agreements, written or oral, made prior to the date hereof between the

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Employee and the Company relating to employment, salary, commission, or other
compensation of any description, future equity participation, pension,
post-retirement benefits, severance or other remuneration, other than the Change
of Control Agreement between IFSC and the Employee dated as of May 16, 2000. In
addition, notwithstanding anything contained herein to the contrary, with
respect to stock options granted to the Employee prior to the date of this
Agreement, the definition of "Change of Control" contained in Section 4(D) of
the Prior Agreement shall continue to apply and shall remain in full force and
effect.

       13. NOTICES. All notices hereunder shall be in writing and shall be
delivered in person, mailed by certified or registered mail, return receipt
requested, or sent by overnight courier, addressed as follows:

       If to the Company, to:        Investors Financial Services Corp.
                                     200 Clarendon Street
                                     Boston, MA   02116-9130
                                     Attention:  Karen C. Keenan


       If to the Employee:           At the most recent address
                                     on file at the Company.

All notices hereunder shall be deemed to have been given either (i) if
personally, upon receipt, (ii) if sent by overnight courier on the next business
day following the day such notice is delivered to the courier service, or (iii)
if sent by registered or certified mail, on the 5th business day following the
day such mailing is made.

       14. COUNTERPARTS. This Agreement may be executed in two counterparts,
each of which shall be deemed to be an original, but all of which together shall
constitute one and the same instrument.

       15. SECTION HEADINGS. The descriptive section headings herein have been
inserted for convenience only and shall not be deemed to define, limit, or
otherwise affect the construction of any provision hereof.

       16. SURVIVAL. Notwithstanding any other provision hereof, the provisions
of Sections 2(D), 4, 5, 17, 18, 19 and 20 shall survive any termination of the
Employees employment and the other provisions of this Agreement.

       17. MITIGATION. The Employee shall not be required to mitigate the amount
of any payment provided for in this Agreement by seeking other employment or
otherwise, nor, other than as provided in Section 4(D) hereof, shall the amount
of any payment provided for herein be reduced by any compensation earned by the
Employee as the result of employment by another employer or by retirement
benefits or insurance payments after the date of termination or otherwise.


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       18. LEGAL EXPENSES. The Company will pay the Employee's reasonable fees
for legal and tax advice and other related expenses associated with the
negotiation and completion of this Agreement, as well as any future amendments
hereto and any disputes arising hereunder, provided, however, in the event of
any dispute arising hereunder, if a court of competent jurisdiction shall render
a final judgment in favor of the Company on the issues in such dispute
hereunder, from which there is no further right of appeal, the Employee shall
reimburse the Company all amounts paid to the Employee under this Section 18
with respect to such dispute.



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       19. INDEMNIFICATION. The Company agrees that the Employee shall be
entitled to indemnification, and advancement of expenses in connection
therewith, as a director, officer and employee of the Company, of IFSC and of
any affiliate of the Company or IFSC to the full extent permitted by applicable
law.

       20. WITHHOLDING. The Company may withhold from any amounts payable under
this Agreement such Federal, state, local or foreign taxes as shall be required
to be withheld pursuant to any applicable law or regulation.




                  [Remainder of Page Intentionally Left Blank]




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<PAGE>


       IN WITNESS WHEREOF, the parties hereto have executed this Employment
Agreement as of the date first above written as an instrument under seal.


Investors Bank & Trust Company              Robert D. Mancuso
By:
   -----------------------------------      ------------------------------------
                                            Signature
Title:
      --------------------------------

Investors Financial Services Corp.
By:
   -----------------------------------

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





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