EXHIBIT 10.25
                              EMPLOYMENT AGREEMENT

EMPLOYMENT  ASSUMPTION  AND AMENDMENT  AGREEMENT,  dated as of  October 25, 1999
(the  "Agreement"),  between  Trenwick Group Inc., a Delaware  corporation  (the
"Company"), and Steven J. Bensinger ("Executive").

WHEREAS,  Chartwell Re Corporation  ("Chartwell") and the Executive entered into
an Employment Agreement,  dated March 6, 1992, as amended from time to time (the
"Employment Agreement"),  a copy of which, including all amendments, is attached
hereto as Exhibit A; and

WHEREAS,  the  Company  has agreed to assume the  Employment  Agreement  and the
Company  and the  Executive  have  agreed  to  make  certain  amendments  to the
Employment Agreement, all as set forth herein.

NOW,  THEREFORE,  the Company and  Executive  hereby  agree that the  Employment
Agreement shall be amended to provide as follows:

1.       Assumption

The Company hereby assumes the  Employment  Agreement as if the Company,  rather
than Chartwell, had been the signatory thereto and the Company and the Executive
hereby consent to the assumption  thereto by the Company and the substitution of
the Company for Chartwell in each place it appears in the  Employment  Agreement
and the  deletion  of  Chartwell  as a party  thereto,  subject to the terms and
conditions of this Agreement.

2.       Term and Non-Competition

The Company and the Executive hereby agree (i) to amend the Employment Agreement
to  extend  the Term  under  Section  2 of the  Employment  Agreement  to end on
December 31, 2000 and (ii) that, notwithstanding Section 10(b) of the Employment
Agreement,  the provisions of Section 10(b)(A) of the Employment Agreement shall
not apply to the Executive on or after the date of any  termination  pursuant to
Section 6 of the Employment Agreement.

3.       Position and Duties.

Section 3 of the Employment Agreement is hereby amendment to read as follows:

         "The  Executive  shall serve as Executive Vice President of the Company
         and shall have such  responsibilities  and duties  (consistent with his
         position  as  Executive  Vice  President)  as may from  time to time be
         assigned to the Executive by the Chief Executive  Officer and the Board
         and all of the  powers  and duties  usually  incident  to the office of
         Executive Vice President.  The Executive shall devote substantially all
         of his  working  time and  efforts to the  business  and affairs of the
         Company,  except for vacations,  illness or  incapacity.  The Executive
         also agrees to serve  without  additional  compensation,  if elected or
         appointed thereto, on the board of directors or as an executive officer
         of any  majority-owned  subsidiary  of the Company.  The  Executive may
         devote reasonable time to (i) insurance associations and charitable and
         civic  organizations,  (ii) managing  personal  investments,  and (iii)
         service  as a  director  or  member  of an  advisory  committee  of any
         corporation  not in  competition  with the Company,  provided  that the
         performance of his duties and responsibilities in such service does not
         interfere   substantially  with  the  performance  of  his  duties  and
         responsibilities under this Agreement."

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4.       Compensation and Benefits:

The term "Base  Salary" set forth in Section  5(a) of the  Employment  Agreement
shall  refer to the Base  Salary  as most  recently  determined  by the Board of
Chartwell  prior to the Merger (as defined in Section  6(a) of this  Agreement).
Section 5(k) of the  Employment  Agreement  shall be deleted in its entirely for
tax years  beginning  after  December 31, 1999.  Section 5(d) of the  Employment
Agreement  shall be amended to read as follows for periods after the date of the
Merger (defined in Section 6(a) of this Agreement):

         "5(d) Automobile.  During the Term, the Company shall provide Executive
         with  an  automobile  appropriate  to  his  status  as  Executive  Vice
         President of the Company and shall reimburse the Executive for the cost
         of reasonable and proper  maintenance,  insurance and parking  expenses
         for such automobile."

5.       Termination for Good Reason:

The  Executive  hereby  agrees  that  any  right he may  have to  terminate  his
employment  for "Good Reason" shall be based on the terms and  conditions of the
Employment Agreement as amended by this Agreement. The Company and the Executive
hereby amend Section 6(d)(iii) to read as follows:

         "(iii)  failure to be elected to the Board of the Company or failure to
         be  elected  President  of  the  Company  (provided  that a  Notice  of
         Termination has not been provided under this Agreement at such time),"

The  following  sentence  shall  be  added  to the  end of  Section  6(d) of the
Employment Agreement:

         "For the purpose of this Section 6(d),  the Company shall be treated as
         curing any failure to elect the Executive  under Section  6(d)(iii) if,
         prior to the earlier of November 1, 2001 or the time that the Executive
         gives Notice of Termination for "Good Reason" under Section  6(c)(iii),
         the Company provides the Executive with a letter signed by the Chairman
         of the Board and the Chief Executive Officer of the Company agreeing to
         place the  Executive's  name before the Board of Directors for election
         as a Director  of the Company  and as  President  of the Company by the
         earlier of the next meeting of the Board of Directors of the Company or
         within thirty (30) days after such written  notice and he is so elected
         within such time period."


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6.       Change of Control

        (a)    The  Company  and the  Executive  agree  that  (i) a  "Change  of
               Control" shall have occurred under the Employment  Agreement,  as
               amended  by  this  Agreement,   upon  the  merger  ("Merger")  of
               Chartwell into the Company ("Chartwell Change of Control"),  (ii)
               the  date  of  the  Chartwell  Change  of  Control  shall  be the
               effective  date  of the  Merger,  (iii)  for the  purpose  of the
               Chartwell  Change of  Control,  the two year  period set forth in
               Section 8(e) of the Employment Agreement shall be extended to end
               on December  31, 2001 and (iv) the term "Base  Salary" in Section
               8(e)(A) shall mean $ 375,000 and the term "highest  annual bonus"
               in Section 8(e)(B)(1) and (2) shall mean $187,500, subject to the
               provision for adjustment for Excise Tax.

        (b)    The  Company and the  Executive  hereby  agree that,  except with
               respect to the Chartwell  Change of Control,  the term "Change of
               Control" shall be amended to read as follows:

                   "For the Purposes of this Agreement, a "Change in Control" of
               the Company shall mean the first to occur of one of the following
               events:

               (i)         The  acquisition, in one  or  more transactions,  of
                           beneficial ownership(within the meaning of  Rule13d-3
                           under  the  Securities  Exchange  Act  of  1934  (the
                           "Exchange Act") by any person or entity or any  group
                           of persons or entities who constitute a group (within
                           the meaning of Rule 13d-3 of the Exchange Act), other
                           than a trustee or other fiduciary holding  securities
                           under an employee  benefit plan of the  Company or  a
                           subsidiary, of any securities of the Company if, as a
                           result of such acquisition, such  person,  entity  or
                           group either(A) beneficially owns (within the meaning
                           of  Rule 13d-3  under the Exchange Act), directly  or
                           indirectly,   more   than   50%  of  the    Company's
                           outstanding voting securities entitled to vote  on  a
                           regular basis for  a majority of  the members of  the
                           Board or (B) otherwise  has  the  ability  to  elect,
                           directly or indirectly, a majority of the members  of
                           the Board;

               (ii)        A change in the  composition of the Board such that a
                           majority   of  the  members  of  the  Board  are  not
                           Continuing Directors.  A "Continuing Director" means,
                           as of any date of  determination,  any  member of the
                           Board  who (A) was a member  of the Board on the date
                           of this  Agreement,  or (B) was nominated and elected
                           to such Board with the affirmative vote of a majority
                           of the  Continuing  Directors who were members of the
                           Board at the time of such nomination or election; or


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               (iii)       The stockholders  of the Company approve (A) a merger
                           or  consolidation  of  the  Company  with  any  other
                           corporation, othe   than a  merger  or  consolidation
                           which would result in the voting  securities  of  the
                           Company    outstanding   immediately   prior  thereto
                           continuing   to  represent   (either   by   remaining
                           outstanding or  by  being   converted   into   voting
                           securities of the surviving entity) at least  50%  of
                           the total voting  power  represented  by  the  voting
                           securities of the Company  or  such  surviving entity
                           outstanding  immediately   after   such   merger   or
                           consolidation, or (B) a plan of complete  liquidation
                           of the Company or an agreement   for   the  sale   or
                           disposition  by   the  Company    (in   one  or  more
                           transactions) of all  or  substantially  all  of  the
                           Company's assets."

(c)            The Company and the Executive  hereby agree that, other than with
               respect  to the  Chartwell  Change  of  Control  and any  amounts
               payable  under  the  Employment  Agreement  with  respect  to the
               Chartwell  Change  of  Control,  Section  8(f) of the  Employment
               Agreement shall be amended to read as follows:

                  "Notwithstanding  any other  provision of this Agreement or of
                  any  other  agreement,  understanding  or  compensation  plan,
                  Executive  shall not be entitled to receive any payment which,
                  taking into account all payments,  rights and benefits,  would
                  be deemed to be an "excess  parachute  payment"  under Section
                  280G (of the Internal  Revenue Code of 1986, as amended),  and
                  the  amount of each  payment  shall be  reduced  to the extent
                  necessary to ensure that the Executive  receives no "parachute
                  payment" in connection with a Change of Control; provided that
                  no such  reduction  shall occur to the extent  that  Executive
                  shall have  elected to defer  receipt of  payments  beyond the
                  dates such payments were otherwise to be made to the Executive
                  ("Payment  Period") and such  deferral  shall have resulted in
                  the present value of such payment not  constituting an "excess
                  parachute  payment".  Any such  election by  Executive,  to be
                  effective  for  purposes  of this  Agreement:  (a)  must be in
                  irrevocable when made, (b) must be made in a writing delivered
                  to the Company prior to the occurrence of a Change of Control,
                  (c) must be for a period not be exceed  five  years  after the
                  date on which the Payment Period would  otherwise end, and (d)
                  must be  concurred  in by the  Company,  on the  basis  of the
                  advice  of its tax  advisors,  as  being  both  necessary  and
                  effective  to reduce the extent to which  payments  to be made
                  hereunder will constitute an "excess parachute  payment".  If,
                  at  any  future  date   following  the  making  of  a  payment
                  hereunder,  it shall have been determined by the IRS that such
                  payment was in excess of the limits set forth in Section 280G,
                  and such  excess  shall  not have been  caused by a  voluntary
                  action of the Executive not required by this  Agreement,  then
                  the  Executive  shall be entitled to receive from the Company,
                  and  the  Company   shall  pay  to  Executive   promptly  upon
                  notification to the Company of such  determination,  an Excise
                  Tax  Adjustment  Payment equal to the amount of all applicable
                  U.S.  federal,  state and local taxes (computed at the maximum
                  marginal rates and including  interest  penalties and any cost
                  of contest or defense and including any applicable Excise Tax)
                  imposed upon the Excise Tax Adjustment Payment."

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(d)            In the  event  that  the  Company  provides  to its  most  senior
               executives,  other than its Chairman and Chief Executive Officer,
               with a Change of Control  Agreement with  provisions  that are in
               the aggregate more  beneficial for these senior  executives  that
               those set forth in the Employment  Agreement,  as amended by this
               Agreement,  then the Company will  immediately  offer the same to
               the  Executive,  in lieu of those  set  forth  in the  Employment
               Agreement, as amended by this Agreement .

7.       Notice:

Section 11 of the Employment shall be amended to read as follows:

"Notice.  For the  purposes of this  Agreement,  notices,  demands and all other
communications  provided for in this Agreement  shall be in writing and shall be
deemed to have been duly given when  delivered  to the  recipient,  addressed as
follows:"

                  If to the Executive:
                        Steven J. Bensinger
                        1049 Fifth Avenue, Apt. 11A
                        New York, NY 10028

                  If to the Company:
                        Trenwick Group Inc.
                        Second Floor
                        One Canterbury Green
                        Stamford, CT 06902
                        Attention:  James W. Billett, Jr.

8.       Termination and Miscellaneous:

This Agreement is conditioned  upon the Merger and, in the event the Merger does
not occur and the  Agreement  and Plan of Merger dated June 21, 1999 between the
Company and Chartwell is terminated for any reason, this Agreement shall be null
and void.  All  capitalized  terms  used in this  Agreement  shall have the same
meaning as called for by the Employment Agreement, unless otherwise indicated in
this  Agreement.  All of the  provisions  of  Sections  13-17 of the  Employment
Agreement shall apply to this Agreement as if set forth herein



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         IN WITNESS  WHEREOF,  the Company and the Executive  have executed this
Agreement as of the date set forth above.

                                          TRENWICK GROUP INC.

                                          By: /s/ James F. Billett, Jr.
                                             ----------------------------
                                          Name:   James F. Billett, Jr.
                                          Title:  Chairman, Presisdent & Chief
                                                  Executive Officer


                                          EXECUTIVE

                                          By: /s/ Steven J. Bensinger
                                             ----------------------------
                                          Name:   Steven J. Bensinger
                                          Title:  President
Chartwell Re Corporation  hereby
consents to the  substitution of
Trenwick Group Inc. as a
party to the Employment Agreement
as of the date of the Merger.

Chartwell Re Corporation

By: /s/ John V. Del Col
   -----------------------------
Name:   John V. Del Col
Title:  Senior Vice President, General Counsel
        and Secetary











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