Exhibit 10.1

      LETTER AGREEMENT CONCERNING EMPLOYMENT, TERMINATION OF EMPLOYMENT AND
                   RELATED AFFILIATION WITH STEPHEN L. BROWN.

                                            February 1, 2001

Mr. Stephen L. Brown

Dear Mr. Brown:

      This letter will confirm the agreement that has been reached between you
and John Hancock Financial Services, Inc. and all of its subsidiary and
affiliated entities (collectively, "John Hancock" or the "Company") concerning
your employment at the Company and the termination of such employment and all
related affiliations.

      1. Your last day of active employment with John Hancock will be May 14,
2001, as of which date you will voluntarily resign and retire from your position
as Chairman of the Company and from all related officerships and directorships
in connection therewith.

      2. During the period from the effective date of this Agreement until May
14, 2001, you shall remain employed by John Hancock as the Company's Chairman.

      3. Following the effective date of this Agreement, in addition to the
obligations set forth in Paragraph 4 hereof, and in consideration of your
commitments as set forth herein, the Company agrees to provide you with the
following compensation and benefits:

            (a) Through May 31, 2001, the Company will continue to compensate
      you at the rate of your current weekly base salary ($19,230.77 per week),
      less legally required deductions for FICA, FUTA, taxes and the like, and
      will likewise continue to provide you with all of the regular employee
      benefits afforded to similarly situated executives of the Company.

            (b) On or around February 5, 2001, you will receive a cash bonus
      under the Incentive Compensation Plan for Employees of John Hancock
      Financial Services, Inc., as amended and restated from time to time by the
      Company for participants generally, based on the Company's economic
      performance in Calendar Year 2000, said bonus (which will be no less than
      $1,910,000.00, less legally required deductions for FICA, FUTA, taxes and
      the like) to be paid to you in the ordinary course and in accordance with
      the regular compensation practices of the Company as the same have been
      applied to you.

            (c) You will receive all payouts in each of the years 2001, 2002 and
      2003, respectively, under John Hancock's Long-Term Incentive Plan for
      Senior Executives, in accordance with and subject to the terms of such
      Plan, as amended and restated from time to time by the Company for
      participants generally. The Long-Term Incentive Plan for Senior Executives
      will be amended prior to your retirement to accomplish this result. It

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Mr. Stephen L. Brown                   -2-                      February 1, 2001


      is agreed and understood that there shall be no other amendments to this
      Plan that diminish or impair your economic rights thereunder.

            (d) On or around February 5, 2001, you will be granted options to
      purchase 1,000,000 shares of John Hancock Financial Services, Inc. common
      stock, in accordance with and subject to the terms of the John Hancock
      Financial Services, Inc. 1999 Long-Term Stock Incentive Plan, and the
      standard stock option agreements applicable generally to Plan participants
      in connection therewith, each as amended and restated from time to time by
      the Company for participants generally. These stock options shall become
      fully vested and thus immediately exercisable upon your retirement from
      John Hancock on May 14, 2001. Provided, however, and notwithstanding any
      contrary provisions of the referenced agreements, the stock options
      granted to you pursuant to this Paragraph 3(d) shall remain fully
      exercisable for a term of five years following the effective date of the
      grant thereof.

            (e) During the first quarter of 2001, you will be eligible to
      receive a matching grant of restricted stock from John Hancock in
      accordance with and subject to the terms of both the Incentive
      Compensation Plan for Employees of John Hancock Financial Services, Inc.,
      as amended and restated from time to time by the Company for participants
      generally, and the Company's Long-Term Incentive Plan for Senior
      Executives, as amended and restated from time to time by the Company for
      participants generally.

      4. Following the effective date of your retirement and resignation from
John Hancock on May 14, 2001, during and through the end of Calendar Year 2002,
and in consideration of your commitments as set forth herein, the Company agrees
to provide you with the following separation compensation and benefits:

            (a) Although you will not continue to earn any regular base salary
      during Calendar Year 2002, you will be eligible to receive a cash bonus
      equal to your "pool" amount for Calendar Year 2001 under the Incentive
      Compensation Plan for Employees of John Hancock Financial Services, Inc.,
      as amended and restated from time to time by the Company for participants
      generally, based on the Company's economic performance in Calendar Year
      2001, said bonus to be paid to you when similarly situated executives of
      the Company receive the same in the ordinary course of their employment.

            (b) You will receive an Incentive Compensation Plan-equivalent cash
      bonus for Calendar Year 2002 in the gross amount of $1,000,000.00, said
      amount to be paid to you in a single lump sum, less legally required
      deductions for FICA, FUTA, taxes and the like, which sum shall be payable
      to you coincident with the Incentive Compensation Plan bonus paid to you
      pursuant to Paragraph 4(a) hereof. If you provide written notice to the
      Company's Vice President of Compensation prior to December 31, 2001 that
      you wish to do so, you may defer all or part of the cash bonus described
      in this paragraph for a period of time not to exceed three years from the
      effective date of this Agreement. Any amount so deferred shall be credited
      with interest determined on the same basis as for deferred amounts under
      the Incentive Compensation Plan for Employees of John Hancock Financial
      Services, Inc., as amended and restated from time to time by the Company
      for participants generally.

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Mr. Stephen L. Brown                   -3-                      February 1, 2001


            (c) You will be eligible to apply up to 50% of the bonus
      compensation paid to you in Calendar Year 2002 under Paragraphs 3(c), 4(a)
      and 4(b) hereof to purchase on a commission-free basis shares of John
      Hancock common stock. The Company will provide you with a matching grant
      of restricted stock in an amount equal to 50% of any shares so purchased
      under the John Hancock Financial Services, Inc. 1999 Long-Term Stock
      Incentive Plan, in accordance with the provisions set forth in the
      Incentive Compensation Plan for Employees of John Hancock Financial
      Services, Inc. and the Company's Long-Term Incentive Plan for Senior
      Executives as such plans are amended and restated from time to time by the
      Company for participants generally.

      5. Health insurance benefits for you, and for your spouse as a dependent,
under the John Hancock Financial Services, Inc. Employee Welfare Plan will
continue without interruption following the effective date of this Agreement,
with the Company providing such primary coverage until you reach age 65. When
you reach age 65, Medicare shall substitute as your primary provider of health
insurance coverage, and all benefits under the Company's Employee Welfare Plan
shall become secondary thereto. Your insurance coverage under the Company's
Employee Welfare Plan shall at all times remain subject to the required retiree
contribution levels customary for retirees with your years of service, and shall
in all respects be in accordance with and subject to the terms of such Plan as
amended and restated from time to time by the Company for participants
generally.

      6. Following your May 14, 2001 retirement and resignation from John
Hancock, and effective June 1, 2001, you shall begin receiving due retirement
benefits under the terms of both the qualified John Hancock Financial Services,
Inc. Pension Plan and the Non-qualified Pension Plan for Home Office and Field
Employees, in each case in accordance with and subject to the terms of such
Plans as the same may be amended and restated from time to time by the Company
for participants generally.

      7. Commencing on May 15, 2001, you shall participate in all other benefit
plans and arrangements, in addition to retirement and medical benefits, but with
the exception of the John Hancock Financial Services, Inc. Senior Officer
Severance Pay Plan, as may be generally available to retired members of the John
Hancock Policy Committee, in accordance with and subject to the terms of such
plans and arrangements as the same may be amended and restated from time to time
by the Company for Policy Committee members generally.

      8. Commencing on May 15, 2001, John Hancock will engage you to provide
consulting services to the Company as an independent contractor, which services
shall consist of providing such counsel and assistance to the CEO (to whom you
will report) and the Policy Committee as may reasonably be requested from time
to time. Under this consulting agreement, which shall continue for a term of two
years (or such other period as may be mutually agreed upon), you agree to
provide up to 200 hours per year in services (including in that total travel
time for services that you are asked to perform outside of Massachusetts, and
including any study or preparation time), and will receive annualized
compensation in an amount equal to $200,000.00,

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Mr. Stephen L. Brown                   -4-                      February 1, 2001


together with reasonable expense reimbursement for travel, lodging, meals and
the like. In this capacity, however, you will be eligible to receive no John
Hancock employee benefits other than those expressly provided for hereunder or
otherwise due you as a retiree of the Company.

      9. Following the effective date of your retirement and resignation from
John Hancock on May 14, 2001, and for the duration of your life or until such
earlier time as may be mutually agreed upon, you will have access to the
following perquisites customarily available to retired Chief Executive Officers
of the Company:

      o     An office comparable in size and location to those of previously
            retired CEOs or, in the alternative, an office located outside of
            the John Hancock complex for which the Company will reimburse you
            quarterly in an amount equal to (i) the fair rental value of the
            office space you would otherwise have received in the John Hancock
            Tower pursuant to this Agreement; and (ii) the actual cost,
            including payroll taxes, insurance and benefits, incurred by you (up
            to $50,000 per year) of a secretary retained by you, provided that
            John Hancock shall not be the employer of, nor have any relationship
            with, nor have any obligations to or with respect to, such secretary
            other than the reimbursement described herein.

      o     A full-time secretary, who will retain her current job grade and
            compensation and benefits eligibility, who would be available for
            service to others in your absence (provided, however, such secretary
            will not be afforded in the event you elect not to maintain an
            office in the John Hancock complex);

      o     Appropriate office furnishings, supplies, periodical subscriptions
            and the like;

      o     Appropriate computer and accessory equipment, black and white and
            color printers, telephone, cellular telephone, photocopier, and fax
            machine, all maintained to preserve currency and compatibility with
            those of other John Hancock users;

      o     Access to a first floor/VIP section parking space in the John
            Hancock garage;

      o     Reasonable access to John Hancock's Security Department for driving
            assignments;

      o     Reasonable access to John Hancock's Catering/Food Services for
            breakfasts and luncheons in the office;

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Mr. Stephen L. Brown                   -5-                      February 1, 2001


      o     Reasonable access to John Hancock's Corporate Travel Services and
            Meeting Management for help in arranging trips;

      o     Renewal of annual memberships in the Algonquin Club and Commercial
            Club; and

      o     Reasonable access to sports tickets over which the Company has
            control, at your cost.

In the event that any of the perquisites described above result in the
imputation of income and the imposition of a state or federal income tax, John
Hancock shall pay to you, upon presentation of reasonable documentation, an
amount sufficient to prevent there being an out-of-pocket cost to you associated
with such tax.

      10. It is agreed and understood that this Agreement will inure to the
benefit of and be binding upon the parties' successors and assigns.

      11. You agree to continue to maintain the strict confidentiality of all
trade secrets, proprietary and confidential business information belonging to
John Hancock. For purposes of this Agreement, all information concerning the
business of the Company shall be considered confidential unless (a) such
information is publicly available prior to the date of this Agreement, or (b)
such information becomes publicly available by reason of acts not attributable
to your breach of this Agreement.

      12. You agree that you will not disparage John Hancock or any of its
affiliates, employees, directors or agents in communications with third parties.
John Hancock, in turn, agrees that neither its Board of Directors nor members of
its senior management team will disparage you in communications with third
parties. John Hancock further agrees that it will provide you with a reasonable
advance review of any internal or external written communications announcing
your planned retirement.

      13. You agree to cooperate with John Hancock with respect to matters
arising during or related to your employment, including but not limited to
cooperation in connection with any litigation, governmental investigation, or
regulatory or other proceeding which may have arisen or which may arise
following the execution of this Agreement. As part of the cooperation agreed to
herein, you shall provide complete and truthful information to the Company and
its attorneys with respect to any matter arising during or related to your
employment. Specifically, you shall make yourself available to meet with Company
personnel and the Company's attorneys, and shall provide to the Company and its
attorneys any and all documentary or other physical evidence pertinent to any
such matter; and, at the Company's request and upon reasonable notice, you shall
travel to such places as the Company may specify (for which the Company will
reimburse you for your reasonable travel and lodging expenses) and provide such
complete and truthful information and evidence to parties whom the Company may
specify. Further, upon the oral request of the Company or its attorneys, you
shall testify, truthfully and accurately, to any such matter in any civil case
to which the Company is a party or in connection with any investigation or
regulatory or other proceeding relating to the Company or its activities.
Finally,

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Mr. Stephen L. Brown                   -6-                      February 1, 2001


you shall promptly notify the Company's General Counsel, within three business
days, of your receipt from any third party or governmental entity of a request
for testimony and/or documents, whether by legal process or otherwise, relating
to any matter arising during or relating to your employment or directorship at
the Company.

      14. In consideration of the benefits to be provided you hereunder, which
benefits you acknowledge are not otherwise due, you hereby release, waive and
forever discharge John Hancock and all those persons, employees, directors,
agents and entities affiliated with it from and against any and all claims,
rights and causes of action now existing, both known and unknown, including but
not limited to all claims of breach of contract or misrepresentation, wrongful
discharge, breach of fiduciary duty or claims of alleged violations of Title VII
of the Civil Rights Act of 1964, the Age Discrimination in Employment Act, the
Fair Labor Standards Act, the Employee Retirement Income Security Act, the
Americans With Disabilities Act, Massachusetts G.L. c. 151B, Massachusetts G.L.
c. 149, ss.148, or any other local, state, or federal law, regulation or other
requirement or any other claim relating to or arising out of your employment
and/or directorship with John Hancock and/or your ownership of Company stock.
You hereby covenant that you will not institute any charge, complaint, or
lawsuit to challenge the validity of this release or to otherwise assert claims
against the Company, and that you will execute and not revoke another such
release in favor of John Hancock in the form appended hereto and marked "A"
coincident with the effective date of your resignation. It is agreed and
understood that the foregoing general release does not waive any of the
following rights: (1) to the pay or benefits to be provided to you as set forth
herein; (2) to enforce the terms of this Agreement; (3) to exercise vested stock
options in accordance with the terms of applicable plans; (4) to access any
currently vested benefits in any John Hancock retirement plan; (5) to raise
counterclaims related to claims that John Hancock has not waived pursuant to
this Agreement; and (6) to avail yourself of any rights to insurance or
indemnification you may have under John Hancock's by-laws or applicable
insurance policies.

      15. In exchange for the commitments set forth herein, John Hancock
voluntarily and forever discharges you from any and all causes of action, rights
or claims now existing, both known and unknown, which the Company may have
against you, except for: (a) claims related to the Company's right to enforce
the terms of this Agreement; (b) claims arising from any criminal or fraudulent
conduct on your part that is reasonably determined by the Company to be contrary
to its interests; (c) claims arising from your violation of state or federal
securities laws or regulations; (d) claims arising after the effective date of
this Agreement; (e) counterclaims related to claims that you have not waived
pursuant to this Agreement; and (f) claims which John Hancock may not release
pursuant to its by-laws or applicable laws and regulations.

      16. Except as otherwise required by law, you and John Hancock shall
maintain the terms of this Agreement in confidence, disclosing the same to no
third parties (other than your spouse and our respective legal and financial
advisers or as otherwise consistent with the legitimate business needs of the
Company) without the express written consent of the other.

      17. John Hancock agrees to reimburse you for reasonable attorney's fees
and expenses incurred in connection with the negotiation of this Agreement.

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Mr. Stephen L. Brown                   -7-                      February 1, 2001


      18. The performance by John Hancock of its commitments hereunder shall be
expressly conditioned on your performance of all of your obligations, including
without limitation those set forth in Paragraphs 11, 12, 13 and 14 (each of
which shall be deemed a material term of this Agreement), set forth herein.
Similarly, your performance of your commitments hereunder shall be expressly
conditioned upon the Company's fulfillment of its obligations set forth herein.
Either party may suspend or terminate its performance hereunder in the event the
other commits a material breach hereof.

      19. You shall be entitled (a) to such rights to indemnification as shall
exist in the Company's articles and/or bylaws and related Board votes, as
amended from time to time, and (b) to coverage under the Company's directors'
and officers' insurance policy and other applicable liability policies, for
causes relating to all actions occurring prior to May 14, 2001, to the extent
set forth in such documents, but in no event greater than the extent to which
such coverage or rights have been or are extended to other officers of the
Company or its subsidiaries or their affiliates. In addition, John Hancock will
indemnify you and hold you harmless in connection with any liabilities
associated with your consulting services under Paragraph 8 hereof.

      20. It is expressly understood that this Agreement does not constitute,
and shall not be construed as constituting, an admission on the part of John
Hancock that it has behaved unlawfully or improperly with respect to you, or as
an admission on your part that you have behaved unlawfully or improperly with
respect to the Company. This Agreement may only be amended or modified by a
writing signed by parties duly authorized to do so.

      21. In the event of any dispute arising out of or relating to this
Agreement or the breach thereof, the parties shall use their best efforts to
settle the dispute by direct negotiations.

            (a) If the dispute is not settled promptly through negotiation, the
      parties shall submit the dispute to mediation under the Commercial
      Mediation Rules of the American Arbitration Association. The parties shall
      each pay their own attorney's fees associated with the mediation, but
      shall share equally the mediation fees.

            (b) Thereafter, any unresolved controversy or claim arising out of
      or relating to this Agreement, or breach thereof, shall be decided in
      binding arbitration by a sole arbitrator in accordance with the Commercial
      Arbitration Rules of the American Arbitration Association, and judgment
      upon the Award rendered by the arbitrator may be entered in any court
      having jurisdiction thereof. In the event of a conflict between such Rules
      and the terms of this Agreement, this Agreement shall govern.

            (c) The arbitrator shall be a Massachusetts lawyer with experience
      in executive compensation matters, and shall be a current equity partner
      or equity owner of a law firm of at least 50 lawyers. The arbitrator shall
      determine the arbitrability of the dispute if it is in controversy. The
      arbitrator may consider and rule on any dispositive- motions submitted by
      the parties.

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Mr. Stephen L. Brown                   -8-                      February 1, 2001


            (d) Except for any stenographer and the arbitrator, attendance at
      the arbitration shall be limited to the parties and their counsel and
      witnesses. Except as necessary for purposes of an action to enforce,
      modify, or vacate the arbitration award, and except to the extent that
      disclosure is required by law, all documents and other information
      submitted to the arbitrator, including any transcript of the proceedings,
      shall be confidential and shall not be disclosed to anyone other than the
      parties and their counsel and financial advisors.

            (e) The arbitration shall be held in Boston, Massachusetts, shall
      commence no later than 90 days after service of the demand, and shall
      proceed from day to day until concluded. The arbitrator shall issue an
      award in writing no later than 30 days after the conclusion of the
      arbitration hearing.

            (f) The parties shall rely solely on the procedures set forth herein
      to resolve any dispute. If any party to this Agreement files an action in
      court (other than an action to compel arbitration or to vacate, modify, or
      enforce the arbitral award) in violation of this Agreement, that party
      shall indemnify the other party for its reasonable attorney's fees and
      costs incurred as a result of such violation. The prevailing party shall
      be entitled to recover reasonable attorney's fees and costs incurred in
      connection with the enforcement of the award if the award is not paid
      within sixty days of issuance, or if the non-prevailing party in the
      arbitration unsuccessfully challenges the award in any court. Each party
      shall bear its own expenses (except as expressly provided above) in
      connection with the arbitration, but the AAA arbitration fees and the
      arbitrator's fee shall be paid by the non-prevailing party.

      22. This Agreement constitutes the entire agreement between you and John
Hancock, and supersedes any other contracts or commitments with respect to your
employment and/or service on the Company's Board of Directors, and/or the
termination thereof, except to the extent expressly provided for herein.

      23. All notices and other communications hereunder shall be in writing and
shall be deemed to have been given three days after having been mailed by
first-class, registered or certified mail, or twelve hours after having been
delivered or sent by facsimile, to the following addresses or to such other
addresses as the parties shall have furnished to each other in writing.

      Stephen L. Brown
      P.O. Box 47
      Boston, MA 02117

      John Hancock Financial Services, Inc.

      Attn:  Wayne Budd, Executive Vice President & General Counsel
             John Hancock Place
             P. O. Box 111
             Boston, MA  02117

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Mr. Stephen L. Brown                   -9-                      February 1, 2001


      24. In order to be certain that this Agreement will resolve any and all
concerns that you might have, John Hancock requests that you carefully consider
its terms, including the general release of claims set forth above. For a period
of seven days following your execution of this Agreement, you may revoke your
acceptance hereof as to the release of claims under the Age Discrimination in
Employment Act, and this Agreement shall not become effective or enforceable as
to the release of such claims until after that seven-day revocation period has
expired.

      25. In signing this Agreement, you acknowledge that you understand its
provisions; that your agreement is knowing and voluntary; that you have been
afforded a full and reasonable opportunity of at least 21 days to consider its
terms and consult with or seek advice from an attorney of your choosing; and
that you have been advised to seek counsel from an attorney and have in fact
done so.

      26. The parties' substantive and procedural rights with respect to this
Agreement shall be governed by the law of the Commonwealth of Massachusetts,
without resort to choice of law or conflict of law principles.

      27. This Agreement is subject to and in all respects conditioned upon the
approval of the John Hancock Board of Directors, and shall not become effective
or enforceable until such Board approval is secured.

      28. This Agreement may be executed in one or more counterparts, each of
which shall be deemed an original, and which together shall be deemed to be one
and the same instrument.

      If the foregoing accurately recites the terms of your agreement with John
Hancock, kindly execute this Agreement in the space provided below and return
the original to me at your convenience.

                                            Very truly yours,



                                            David F. D'Alessandro
                                            Chief Executive Officer


ACCEPTED AND AGREED TO:


--------------------------------
Stephen L. Brown
Dated:

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                                       "A"

                                RELEASE OF CLAIMS

FOR AND IN CONSIDERATION OF the special payments to be made to me in connection
with my separation from employment and membership on the Board of Directors and
related affiliations, as set forth in the Agreement between me and John Hancock
Financial Services, Inc. and all of its subsidiaries and affiliates (the
"Company"), dated as of February 1, 2001 (the "Agreement") I, on my own behalf
and on behalf of my heirs, beneficiaries and representatives and all others
connected with me, hereby forever release, waive and discharge any and all
causes of action or claims against the Company, its parent, subsidiary and
affiliated organizations and the respective past, present and future directors,
officers, agents, employees, successors and assigns of such organizations, that
I have had, now have or may have in any way related to or arising out of my
employment or other affiliations with John Hancock, including claims pursuant to
any federal, state or local employment laws, regulations, executive orders or
other requirements, including without limitation Title VII of the Civil Rights
Act of 1964, the Age Discrimination in Employment Act, the Older Workers Benefit
Protection Act, the Americans with Disabilities Act of 1990, the Employee
Retirement Income Security Act, and Mass. G.L. c. 151B, all as they may have
been amended.

      In signing this Release of Claims, I acknowledge that I have had a full
and reasonable opportunity of at least twenty-one (21) days to consider the
terms of this Release of Claims, that I was encouraged by John Hancock to
consult with an attorney prior to signing this Release of Claims, and that I am
signing this Release of Claims voluntarily and with a full understanding of its
terms.

      I understand that I may revoke this Release of Claims as to rights and
claims under the Age Discrimination in Employment Act (ADEA) at any time within
seven (7) days of the date of my signing by written notice to the Company, and
that this Release of Claims as to rights and claims under the ADEA will take
effect only upon the expiration of such seven-day revocation period and only if
I have not timely revoked it. As to all other claims, this Release of Claims
shall be effective upon execution.

      Intending to be legally bound, I have set my hand and seal on the date
written below.


                                  Signature:     ______________________________
                                                 Stephen L. Brown


                                        Dated:   ______________________________