Exhibit 10.2

Trenwick Group Ltd.                                               LOM Building
                                                                  27 Reid Street
[LOGO]                                                            Hamilton HM11
                                                                  Bermuda

August 26, 2002
Mr. W. Marston Becker
48 Ledyard Road

West Hartford, CT 06117-1708

Dear Mr. Becker:

This letter agreement (this "Agreement") will confirm the understanding between
Trenwick Group Ltd. (the "Company") and you, pursuant to which you have been
engaged by the Company to provide services as its Acting Chairman of the Board
of Directors and Acting Chief Executive Officer.

You shall perform the duties and activities customarily associated with the
Chairman and Chief Executive Officer of the Company and you shall have full
authority to conduct the affairs of the Company during the term of this
Agreement. Your duties shall include but not be limited to the ability to enter
into contracts and other agreements binding the Company, hiring and dismissal of
employees, engagement of independent contractors to work for the Company, and
representation of the Company before regulatory authorities and rating agencies.

The term of this Agreement and your engagement hereunder shall extend from
August 15, 2002 through the earliest of (a) your death or disability, (b) the
mutual agreement of you and the Company or (c) thirty calendar days following
delivery of written notice of termination of this Agreement by you or the
Company.

      Notwithstanding expiration or termination of this Agreement, it is agreed
      that the provisions concerning confidentiality (Section 6),
      indemnification (Sections 5 and 8), ownership of work product (Section 7),
      dispute resolution (Section 10) and the Company's obligations to pay fees
      and reimburse expenses earned or incurred prior to the termination of this
      Agreement (Section 3) shall survive any such expiration or termination.

As compensation for the services hereunder, the Company will pay you, beginning
on August 15, 2002, a monthly fee of $50,000, which shall be paid in arrears on
or before the 15th calendar day of each month following the month in which such
fee is earned. This monthly fee shall be reduced pro rata for (a) partial months
worked and (b) the time which you spend on other activities not related to work
for the Company. You shall report at the end of each calendar month the
proportion of your working time spent on Company business during such calendar
month. It is our mutual anticipation that you will spend at least 75% of your
working time on the Company's business.

      The Company shall reimburse you monthly for your reasonable out-of-pocket
      expenses incurred or accrued during the period of or in connection with
      your engagement notwithstanding the termination of this Agreement. You
      shall report and account for your expenses monthly on the Company's
      standard expense account forms and be reimbursed by the Company within 30
      calendar days of submission of such expense account forms to the Company.


                                      -35-
<PAGE>

You shall not be entitled to any Company benefits or other benefits as may
accrue to a full or part-time employee of the Company.

In performing services and duties hereunder, you shall do so as an independent
contractor and you are not, and are not to be deemed, an employee of the Company
or any other person acting on behalf of the Company. You shall be responsible
for meeting any legal requirements imposed on you or any person acting on your
behalf as a result of this Agreement, including but not limited to the filing of
income tax returns and the payment of taxes; and you agree to indemnify the
Company for the failure to do so, if the Company is required to make any such
payment otherwise due by you.

To the extent that you obtain non-public information about the Company's or its
affiliates' business practices and plans, including but not limited to, business
strategies, marketing strategies, technical information, systems information,
product development, service development and customers ("Confidential
Information"), then all such Confidential Information disclosed to you shall be
received by you in confidence for purposes of this Agreement. You shall not
disclose, disseminate, publish, communicate or divulge any Confidential
Information to anyone outside the Company, or to any employee of the Company not
having reasonable need for access to such information, unless the Company
expressly consents to such disclosure in writing or as may be required by law.
You agree that all Confidential Information within your possession upon
termination of this Agreement shall be returned promptly to the Company. You
understand and agree that money damages will not be sufficient as a remedy for
any breach of this Section and that the Company shall be entitled to equitable
relief, including injunction and specific performance, as a remedy for any
breach of this Section.

All work product created by you on behalf of the Company during the term of this
Agreement shall be the sole property of the Company, and you shall not have any
license or other right, express or implied, to such work product.

In consideration for your work on behalf of the Company, the Company shall
indemnify and hold you harmless from and against any and all claims, damages or
liabilities arising out of your engagement as Acting Chairman and Acting Chief
Executive Officer, unless a judgment or other final adjudication establishes
that your acts or omissions were in bad faith or involved intentional misconduct
or a knowing violation of law. Costs and expenses (including attorney's fees)
incurred by you in defending or investigating any action, suit, proceeding or
investigation shall be paid by the Company, in advance of final disposition of
such matter, upon receipt of your written undertaking to repay any such amounts
if it is ultimately determined that you are not entitled to indemnification
hereunder.


                                      -36-
<PAGE>

For the purposes of this Agreement, notices, demands and all other
communications shall be in writing and shall be deemed to have been duly given
when delivered to the recipient at one of the following addresses:

     If to you:
                  48 Ledyard Road
                  West Hartford, CT 06117

         If to the Company:
                  One Canterbury Green
                  Stamford, Connecticut 06901
                  Attention:  General Counsel

      or to such other address as any party may have furnished to the other in
      writing.

Except as otherwise set forth in Section 6 herein with respect to the Company's
remedy for any breach of Section 6, all controversies, claims, or disputes
arising out of or related to this Agreement, shall be settled by arbitration in
the State of Connecticut, as the sole and exclusive remedy of either party, and
judgment upon such award rendered by the arbitrator(s) may be entered in any
court of competent jurisdiction. In the event that a court of competent
jurisdiction determines that arbitration is not appropriate for the adjudication
of any claim, you hereby waive your right to a jury trial.

      One arbitrator shall be chosen by you, the other by the Company, and an
      umpire shall be chosen by the two arbitrators, all of whom shall be active
      or retired disinterested executive officers of insurance or reinsurance
      companies. In the event that either party shall fail to choose an
      arbitrator within 30 days following a written request by the other party
      to do so, the requesting party may choose two arbitrators who shall in
      turn choose an umpire. If the two arbitrators fail to agree on the
      selection of an umpire within 30 days following their appointment, each
      arbitrator shall name three nominees, of whom the other shall decline two,
      and the decision shall be made by drawing lots.

      Each party shall bear the expense of its own arbitrator, and shall jointly
      and equally bear with the other the expense of the umpire.


                                      -37-
<PAGE>

If any provision of this Agreement shall, to any extent, now or hereafter be or
become invalid or unenforceable, the remainder of this Agreement shall not be
affected thereby and every other provision of this Agreement shall be valid and
enforceable, to the fullest extent permitted by law.

No provision of this Agreement may be modified, waived or discharged unless such
waiver, modification or discharge is agreed to in writing signed by the parties.
No waiver by either party at any time of any breach by the other party hereto
of, or compliance with, any condition or provision of this Agreement to be
performed by such other party shall be deemed a waiver of similar or dissimilar
provisions or conditions at the same or at any prior or subsequent time.

This Agreement sets forth the entire agreement of the parties hereto in respect
of the subject matter contained herein and supersedes all prior agreements,
promises, covenants, arrangements, communications, representations or
warranties, whether oral or written, by any officer, employee or representative
of any party hereto.

Neither party to this Agreement can assign his or its rights or obligations
under this Agreement without the prior written consent of the other party to
this Agreement.

This Agreement shall be governed by and construed in accordance with the laws of
the State of Connecticut without regard to the conflicts of law provisions
thereof. This Agreement may be signed in any number of counterparts, each of
which shall be an original, but all of which together shall constitute one and
the same instrument.

If the foregoing correctly sets forth the understanding and agreement between
you and the Company, please sign and return one original executed copy of this
Agreement.

                            Trenwick Group Ltd.

                            /s/ Clement S. Dwyer, Jr.
                            -----------------------------------------
                            By: Clement S. Dwyer, Jr.
                                Chairman of the Compensation Committee

Confirmed and Agreed as of the date first written above:


/s/ W. Marston Becker
---------------------------------
W. Marston Becker


                                      -38-