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                                                                   Exhibit 10.21
                                                                   -------------
                            EMPLOYMENT AGREEMENT
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         AGREEMENT by and among Bank of Boston Corporation, a Massachusetts
corporation ("Bank of Boston" or the "Company"), BayBanks, Inc., a Massachusetts
corporation ("BayBanks") and Donald L. Isaacs (the "Executive"), dated as of the
12th day of December, 1995.

         The Boards of Directors of BayBanks and Bank of Boston have determined
that it is in the best interests of BayBanks, the Company and their shareholders
to assure that BayBanks will have the continued dedication of the Executive
pending the merger of the Company and BayBanks (the "Merger") pursuant to the
Agreement and Plan of Merger dated as of December 12, 1995 and to provide the
surviving corporation after the Merger with continuity of management. Therefore,
in order to accomplish these objectives, the Boards of Directors of BayBanks and
Bank of Boston have caused BayBanks and Bank of Boston to enter into this
Agreement.

         NOW, THEREFORE, IT IS HEREBY AGREED AS FOLLOWS:

         1.  EFFECTIVE DATE.  The "Effective Date" shall mean the effective 
date of the Merger.

         2.  EMPLOYMENT PERIOD.  The Company agrees to employ the Executive or
cause the Executive to be employed, and the Executive hereby agrees to remain in
the employ of the Company or its affiliates subject to the terms and conditions
of this Agreement, for the period commencing on the Effective Date and ending on
April 1, 1997 (the "Employment Period").

         3.  TERMS OF EMPLOYMENT.  (a)  POSITION AND DUTIES.  (i) (A)  During 
the Employment Period, the Executive shall serve as Vice Chairman of
BayBank  of Boston N.A. or such other entity as is the most significant New
England bank of Bank of Boston with responsibility for regional banking
integration and overhead allocation reporting to the office of the Executive
Officer of the Company and with such other authority, duties and
responsibilities as are commensurate with such position and (B) the Executive's
services shall be performed in Boston, Massachusetts.

                  (ii) During the Employment Period, and excluding any periods
of vacation and sick leave to which the Executive is entitled, the Executive
agrees to devote reasonable attention and time during normal business hours to
the business and affairs of the Company and, to the extent necessary to
discharge the responsibilities assigned to the Executive hereunder, to use the
Executive's reasonable best efforts to perform faithfully and efficiently such
responsibilities. However, the Company acknowledges that the Executive shall be
entitled to a sabbatical during 1996 of approximately four months. During the
Employment Period it shall not be a violation of this Agreement for the


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Executive to (A) serve on corporate, civic or charitable boards or committees,
(B) deliver lectures, fulfill speaking engagements or teach at educational
institutions and (C) manage personal investments, so long as such activities do
not significantly interfere with the performance of the Executive's
responsibilities as an employee of the Company in accordance with this
Agreement. It is expressly understood and agreed that to the extent that any
such activities have been conducted by the Executive prior to the Effective
Date, the continued conduct of such activities (or the conduct of activities
similar in nature and scope thereto) subsequent to the Effective Date shall not
thereafter be deemed to interfere with the performance of the Executive's
responsibilities to the Company.

         (b)  COMPENSATION.  (i) BASE SALARY. During the Employment Period, the
Executive shall receive an annual base salary ("Annual Base Salary"), which
shall be paid at a monthly rate, at least equal to twelve times the highest
monthly base salary paid or payable, including any base salary which has been
earned but deferred, to the Executive by the Company and its affiliated
companies in respect of the twelve-month period immediately preceding the month
in which the Effective Date occurs. During the Employment Period, the Annual
Base Salary shall be reviewed no more than 12 months after the last salary
increase awarded to the Executive prior to the Effective Date and thereafter at
least annually. Any increase in Annual Base Salary shall not serve to limit or
reduce any other obligation to the Executive under this Agreement. Annual Base
Salary shall not be reduced after any such increase and the term Annual Base
Salary as utilized in this Agreement shall refer to Annual Base Salary as so
increased. As used in this Agreement, the term "Affiliated Companies" shall
include any company controlled by, controlling or under common control with the
Company.

                  (ii)  INCENTIVE, SAVINGS AND RETIREMENT PLANS.  During
the Employment Period, the Executive shall be entitled to participate
in all incentive, savings and retirement plans, practices, policies and
programs applicable generally to other peer executives of the Company and its
affiliated companies, including, without limitation, eligibility for a pro rata
bonus for the year in which the Effective Date occurs; provided, however, at
the end of the Employment Period, Executive shall be deemed to have sufficient
age and service to equal 75 years under BayBank's Supplemental Executive
Retirement Plan, as in effect immediately prior to the Effective Date (the
"SERP").

                 (iii)  WELFARE BENEFIT PLANS.  During the Employment Period, 
the Executive and/or the Executive's family, as the case may be, shall be 
eligible for participation in and shall receive all benefits under
welfare benefit plans, practices, policies and programs provided by the Company
and its affiliated companies (including, without limitation, medical,
prescription, dental, disability, employee life, group life, accidental death
and travel accident insurance plans and programs) to the extent applicable
generally to other peer executives of the Company and

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its affiliated companies. For purposes of determining the Executive's right to
participate and level of participation in any retiree health or similar plan of
the Company, Executive's service with BayBanks shall be deemed to be service
with the Company for all purposes.

                 (iv)  EXPENSES.  During the Employment Period, the Executive
shall be entitled to receive prompt reimbursement for all reasonable expenses
incurred by the Executive in accordance with the Company's policies.

                  (v)  FRINGE BENEFITS.  During the Employment Period, the
Executive shall be entitled to fringe benefits, including, without limitation,
payment of club dues, and, if applicable, use of an automobile and payment of
related expenses, to the extent applicable generally to other peer executives of
the Company and its affiliated companies.

                 (vi)  OFFICE AND SUPPORT STAFF.  During the Employment Period,
the Executive shall be entitled to an office or offices of a size and with
furnishings and other appointments as provided generally at any time thereafter
with respect to other peer executives of the Company and its affiliated
companies.

                (vii)  VACATION.  During the Employment Period, the Executive
shall be entitled to paid vacation in accordance with the plans, policies,
programs and practices of the Company and its affiliated companies as in effect
generally at any time with respect to other peer executives of the Company and
its affiliated companies.

         4. TERMINATION OF EMPLOYMENT.  (a) DEATH OR DISABILITY.  The 
Executive's employment shall terminate automatically upon the Executive's death
during the Employment Period. If the Company determines in good faith that 
the Disability of the Executive has occurred during the Employment Period 
(pursuant to the definition of Disability set forth below), it may give 
to the Executive written notice in accordance with Section 11(b) of this 
Agreement of its intention to terminate the Executive's employment. In such 
event, the Executive's employment with the Company shall terminate effective 
on the 30th day after receipt of such notice by the Executive (the "Disability
Effective Date"), provided that, within the 30 days after such receipt, the 
Executive shall not have returned to full-time performance of the Executive's 
duties. For purposes of this Agreement, "Disability" shall mean the absence of
the Executive from the Executive's duties with the Company on a full-time 
basis for 180 consecutive business days as a result of incapacity due to 
mental or physical illness which is determined to be total and permanent by a 
physician selected by the Company or its insurers and acceptable to the 
Executive or the Executive's legal representative.

         (b)  CAUSE.  The Company may terminate the Executive's employment 
during the Employment Period for Cause.  For purposes of this Agreement, 
"Cause" shall mean:

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                 (i)  the continued failure of the Executive to perform
substantially the Executive's duties with the Company or one of its affiliates
(other than any such failure resulting from incapacity due to physical or mental
illness), after a written demand for substantial performance is delivered to the
Executive by the Board or the Chief Executive Officer of the Company which
specifically identifies the manner in which the Board or Chief Executive Officer
believes that the Executive has not substantially performed the Executive's
duties, or

                (ii)  the willful engaging by the Executive in illegal conduct 
or gross misconduct which is materially and demonstrably injurious to the 
Company, or

               (iii)  conviction of a felony or guilty or nolo contendere plea 
by the Executive with respect thereto, or

                (iv)  a material breach of the covenants contained in Section 9.

For purposes of this provision, no act or failure to act, on the part of the
Executive, shall be considered "willful" unless it is done, or omitted to be
done, by the Executive in bad faith or without reasonable belief that the
Executive's action or omission was in the best interests of-the Company. Any
act, or failure to act, based upon authority given pursuant to a resolution duly
adopted by the Board or upon the instructions of the Chief Executive Officer or
a senior officer of the Company or based upon the advice of counsel for the
Company shall be conclusively presumed to be done, or omitted to be done, by the
Executive in good faith and in the best interests of the Company. The cessation
of employment of the Executive shall not be deemed to be for Cause unless and
until there shall have been delivered to the Executive a copy of a resolution
duly adopted by the affirmative vote of not less than two-thirds of the entire
membership of the Board at a meeting of the Board called and held for such
purpose (after reasonable notice is provided to the Executive and the Executive
is given an opportunity, together with counsel, to be heard before the Board),
finding that, in the good faith opinion of the Board, the Executive is guilty of
the conduct described in subparagraph (i) or (ii) above, and specifying the
particulars thereof in detail.

         (c)  GOOD REASON.  The Executive's employment may be terminated by 
the Executive for Good Reason.  For purposes of this Agreement, "Good Reason" 
shall mean in the absence of a written consent of the Executive:

                 (i)  the assignment to the Executive of any duties inconsistent
in any material respect with the Executive's position (including status,
offices, titles and reporting requirements), authority, duties or
responsibilities as contemplated by Section 3(a) of this Agreement, or any other
action by the Company which results in a material diminution in such position,
authority, duties or responsibilities, excluding

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for this purpose an isolated, insubstantial and inadvertent action not taken in
bad faith and which is remedied by the Company promptly after receipt of notice
thereof given by the Executive;

                 (ii)  any material failure by the Company to comply with any of
the provisions of Section 3(b) of this Agreement, other than an isolated,
insubstantial and inadvertent failure not occurring in bad faith and which is
remedied by the Company promptly after receipt of notice thereof given by the
Executive;

                (iii)  the Company's requiring the Executive to be based at any
office or location more than 35 miles from that provided in Section 3(a)(i)(B)
hereof or the Company's requiring the Executive to travel on Company business to
a substantially greater extent than required immediately prior to the Effective
Date;

                 (iv)  any purported termination by the Company of the
Executive's employment otherwise than as expressly permitted by this Agreement; 
or

                  (v)  any failure by the Company to comply with and satisfy 
Section 10(c) of this Agreement.

For purposes of this Section 4(c), any good faith determination of "Good Reason"
made by the Executive shall be conclusive. Anything in this Agreement to the
contrary notwithstanding, a termination by the Executive for any reason during
the 30-day period immediately following the first anniversary of the Effective
Date shall be deemed to be a termination for Good Reason for all purposes of
this Agreement.

         (d)  NOTICE OF TERMINATION.  Any termination by the Company for Cause,
or by the Executive for Good Reason, shall be communicated by Notice of 
Termination to the other party hereto given in accordance with Section 11(b) of
this Agreement. For purposes of this Agreement, a "Notice of Termination" means
a written notice which (i) indicates the specific termination provision in this
Agreement relied upon, (ii) to the extent applicable, sets forth in reasonable
detail the facts and circumstances claimed to provide a basis for termination of
the Executive's employment under the provision so indicated and (iii) if the
Date of Termination (as defined below) is other than the date of receipt of such
notice, specifies the termination date (which date shall be not more than thirty
days after the giving of such notice). The failure by the Executive or the
Company to set forth in the Notice of Termination any fact or circumstance which
contributes to a showing of Good Reason or Cause shall not waive any right of
the Executive or the Company, respectively, hereunder or preclude the Executive
or the Company, respectively, from asserting such fact or circumstance in
enforcing the Executive's or the Company's rights hereunder.

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         (e)  DATE OF TERMINATION.  "Date of Termination" means (i) if the
Executive's employment is terminated by the Company for Cause, or by the
Executive for Good Reason, the date of receipt of the Notice of Termination or
any later date specified therein within 30 days of such notice, as the case may
be, (ii) if the Executive's employment is terminated by the Company other than
for Cause or Disability, the Date of Termination shall be the date on which the
Company notifies the Executive of such termination and (iii) if the Executive's
employment is terminated by reason of death or Disability, the Date of
Termination shall be the date of death of the Executive or the Disability
Effective Date, as the case may be.

         5.  OBLIGATIONS OF THE COMPANY UPON TERMINATION.  (a)  GOOD REASON 
OTHER THAN FOR CAUSE, DEATH OR DISABILITY.  If, during the Employment Period, 
the Company shall terminate the Executive's employment other than for Cause or 
Disability or the Executive shall terminate employment for Good Reason:

                  (i)  the Company shall pay to the Executive in a lump sum in 
cash within 30 days after the Date of Termination the aggregate of the 
following amounts:

                           (A)  the sum of (1) the Executive's Annual Base
Salary through the Date of Termination to the extent not theretofore paid, and
(2) to the extent not previously paid, the product of (x) the maximum annual
incentive or similar award for which the Executive is eligible immediately prior
to the Effective Date, or if greater, any annual bonus paid during the
Employment Period (the "Eligible Annual Bonus") and (y) a fraction, the
numerator of which is the number of days in the fiscal year in which the Date of
Termination occurs through the Date of Termination, and the denominator of which
is 365 and (3) any unused sick pay, in each case to the extent not theretofore
paid (the sum of the amounts described in clauses (1), (2), and (3) shall be
hereinafter referred to as the "Accrued Obligations"); and

                           (B)  the amount equal to the product of (1) the
number of years (including fractions thereof) from the Date of Termination until
the last day of the Employment Period (the "Continuation Period") and (2) the
sum of (x) the Executive's Annual Base Salary and (y) the Eligible Annual Bonus;
and

                 (ii)  the Executive's benefit under the Company's SERP shall be
increased to the benefit that would be payable thereunder if, utilizing
actuarial assumptions no less favorable to the Executive than those in effect
immediately prior to the Effective Date, the sum of the Executive's age and
years of service under the SERP equaled 75, assuming for this purpose that (x)
all accrued benefits are fully vested, (y) the Executive's compensation during
the additional period required to generate sufficient years of age and service
is that required by Section 3(b)(i) and his annual bonus during such period is
equal to the

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Eligible Annual Bonus, and (z) the Executive is 55 years old on the Date of 
Termination; and

                 (iii)  for the Continuation Period, or such longer period as
may be provided by the terms of the appropriate plan, program, practice or
policy, the Company shall continue benefits to the Executive and/or the
Executive's family at least equal to those which would have been provided to
them in accordance with the plans, programs, practices and policies described in
Section 3(b)(iii) of this Agreement if the Executive's employment had not been
terminated or, if more favorable to the Executive, as in effect generally at any
time thereafter with respect to other peer executives of the Company and its
affiliated companies and their families, provided, however, that if the
Executive becomes reemployed with another employer and is eligible to receive
medical or other welfare benefits under another employer provided plan, the
medical and other welfare benefits described herein shall be secondary to those
provided under such other plan during such applicable period of eligibility. For
purposes of determining eligibility (but not the time of commencement of
benefits) of the Executive for retiree benefits pursuant to such plans,
practices, programs and policies, the Executive shall be considered to have
remained employed until the end of the Continuation Period and to have retired
on the last day of such period;

                  (iv)  the Company shall, at its sole expense as incurred,
provide the Executive with outplacement services the scope and provider of which
shall be selected by the Executive in his sole discretion;

                   (v)  to the extent not theretofore paid or provided, the
Company shall timely pay or provide to the Executive any other amounts or
benefits required to be paid or provided or which the Executive is eligible to
receive under any plan, program, policy or practice or contract or agreement of
the Company and its affiliated companies (such other amounts and benefits shall
be hereinafter referred to as the "Other Benefits"); and

                  (vi)  the Executive shall be given service credit for unused
sick pay under all of the benefit plans in which the Executive participates for
purposes of determining eligibility and the amount of benefits thereunder; in
the event such credit can not be given under such plans, the Executive shall be
provided with cash equivalent thereof.

         (b)  DEATH.  If the Executive's employment is terminated by 
reason of the Executive's death during the Employment Period, this
Agreement shall terminate without further obligations to the Executive's legal
representatives under this Agreement, other than for payment of Accrued
Obligations and the timely payment or provision of Other Benefits.  Accrued
Obligations shall be paid to the Executive's estate or beneficiary, as
applicable, in a lump sum in cash within 30 days of the Date of Termination. 
With

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respect to the provision of Other Benefits, the term Other Benefits as utilized
in this Section 5(b) shall include death benefits as in effect on the date of
the Executive's death with respect to other peer executives of the Company and
its affiliated companies and their beneficiaries.

         (c)  DISABILITY.  If the Executive's employment is terminated by reason
of the Executive's Disability during the Employment Period, this Agreement shall
terminate without further obligations to the Executive, other than for payment
of Accrued Obligations and the timely payment or provision of Other Benefits.
Accrued Obligations shall be paid to the Executive in a lump sum in cash within
30 days of the Date of Termination. With respect to the provision of Other
Benefits, the term Other Benefits as utilized in this Section 5(c) shall
include, and the Executive shall be entitled after the Disability Effective Date
to receive, disability and other benefits as in effect at any time thereafter
generally with respect to other peer executives of the Company and its
affiliated companies and their families.

         (d)  CAUSE; OTHER THAN FOR GOOD REASON.  If the Executive's employment
shall be terminated for Cause or the Executive terminates his employment without
Good Reason during the Employment Period, this Agreement shall terminate without
further obligations to the Executive other than the obligation to pay to the
Executive (x) his Annual Base Salary through the Date of Termination, (y) the
amount of any compensation previously deferred by the Executive, and (z) Other
Benefits, in each case to the extent theretofore unpaid.

         6.  NON-EXCLUSIVITY OF RIGHTS.  Nothing in this Agreement shall prevent
or limit the Executive's continuing or future participation in any plan,
program, policy or practice provided by the Company or any of its affiliated
companies and for which the Executive may qualify, nor, subject to Section
11(f), shall anything herein limit or otherwise affect such rights as the
Executive may have under any contract or agreement with the Company or any of
its affiliated companies. Amounts which are vested benefits or which the
Executive is otherwise entitled to receive under any plan, policy, practice or
program of or any contract or agreement with the Company or any of its
affiliated companies at or subsequent to the Date of Termination shall be
payable in accordance with such plan, policy, practice or program or contract or
agreement except as explicitly modified by this Agreement.

         7.  FULL SETTLEMENT.  The Company's obligation to make the payments
provided for in this Agreement and otherwise to perform its obligations
hereunder shall not be affected by any set-off, counterclaim, recoupment,
defense or other claim, right or action which the Company may have against the
Executive or others. In no event shall the Executive be obligated to seek other
employment or take any other action by way of mitigation of the amounts payable
to the Executive under any of the provisions of this Agreement and, except as
provided in Section 5(a)(ii), such

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amounts shall not be reduced whether or not the Executive obtains other
employment. The Company agrees to pay as incurred, to the full extent permitted
by law, all legal fees and expenses which the Executive may reasonably incur as
a result of any contest (regardless of the outcome thereof) by the Company, the
Executive or others of the validity or enforceability of, or liability under,
any provision of this Agreement or any guarantee of performance thereof
(including as a result of any contest by the Executive about the amount of any
payment pursuant to this Agreement), plus in each case interest on any delayed
payment at the applicable Federal rate provided for in Section 7872(f)(2)(A) of
the Internal Revenue Code of 1986, as amended (the "Code").

         8.       Certain Additional Payments by the Company.
                  ------------------------------------------

         (a)  Anything in this Agreement to the contrary notwithstanding and
except as set forth below, in the event it shall be determined that any payment
or distribution by the Company to or for the benefit of the Executive (whether
paid or payable or distributed or distributable pursuant to the terms of this
Agreement or otherwise, but determined without regard to any additional payments
required under this Section 8) (a "Payment") would be subject to the excise tax
imposed by Section 4999 of the Code or any interest or penalties are incurred by
the Executive with respect to such excise tax (such excise tax, together with
any such interest and penalties, are hereinafter collectively referred to as the
"Excise Tax"), then the Executive shall be entitled to receive an additional
payment (a "Gross-Up Payment") in an amount such that after payment by the
Executive of all taxes (including any interest or penalties imposed with respect
to such taxes), including, without limitation, any income taxes (and any
interest and penalties imposed with respect thereto) and Excise Tax imposed upon
the Gross-Up Payment, the Executive retains an amount of the Gross-Up Payment
equal to the Excise Tax imposed upon the Payments. Notwithstanding the foregoing
provisions of this Section 8(a), if it shall be determined that the Executive is
entitled to a Gross-Up Payment, but that the Payments do not exceed 110% of the
greatest amount (the "Reduced Amount") that could be paid to the Executive such
that the receipt of Payments would not give rise to any Excise Tax, then no
Gross-Up Payment shall be made to the Executive and the Payments, in the
aggregate, shall be reduced to the Reduced Amount.

         (b)  Subject to the provisions of Section 8(c), all determinations
required to be made under this Section 8, including whether and when a Gross-Up
Payment is required and the amount of such Gross-Up Payment and the assumptions
to be utilized in arriving at such determination shall be made by Coopers &
Lybrand LLC or such other certified public accounting firm reasonably acceptable
to the Company as may be designated by the Executive (the "Accounting Firm")
which shall provide detailed supporting calculations both to the Company and the
Executive within 15 business days of the receipt of notice from the Executive
that there has been a Payment, or such earlier time

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as is requested by the Company. In the event that the Accounting Firm is serving
as accountant or auditor for the individual, entity or group effecting the
Change of Control, the Executive shall appoint another nationally recognized
accounting firm reasonably acceptable to the Company to make the determinations
required hereunder (which accounting firm shall then be referred to as the
Accounting Firm hereunder). All fees and expenses of the Accounting Firm shall
be borne solely by the Company. Any Gross-Up Payment, as determined pursuant to
this Section 8, shall be paid by the Company to the Executive within five days
of (i) the later of the due date for the payment of any Excise Tax, and (ii) the
receipt of the Accounting Firm's determination. Any determination by the
Accounting Firm shall be binding upon the Company and the Executive. As a result
of the uncertainty in the application of Section 4999 of the Code at the time of
the initial determination by the Accounting Firm hereunder, it is possible that
Gross-Up Payments which will not have been made by the Company should have been
made ("Underpayment"), consistent with the calculations required to be made
hereunder. In the event that the Company exhausts its remedies pursuant to
Section 8(c) and the Executive thereafter is required to make a payment of any
Excise Tax, the Accounting Firm shall determine the amount of the Underpayment
that has occurred and any such Underpayment shall be promptly paid by the
Company to or for the benefit of the Executive.

         (c)  The Executive shall notify the Company in writing of any claim by
the Internal Revenue Service that, if successful, would require the payment by
the Company of the Gross-Up Payment. Such notification shall be given as soon as
practicable but no later than ten business days after the Executive is informed
in writing of such claim and shall apprise the Company of the nature of such
claim and the date on which such claim is requested to be paid. The Executive
shall not pay such claim prior to the expiration of the 30-day period following
the date on which it gives such notice to the Company (or such shorter period
ending on the date that any payment of taxes with respect to such claim is due).
If the Company notifies the Executive in writing prior to the expiration of such
period that it desires to contest such claim, the Executive shall:

                  (i)  give the Company any information reasonably requested 
by the Company relating to such claim,

                 (ii)  take such action in connection with contesting such claim
as the Company shall reasonably request in writing from time to time, including,
without limitation, accepting legal representation with respect to such claim by
an attorney reasonably selected by the Company,

                (iii)  cooperate with the Company in good faith in order 
effectively to contest such claim, and

                 (iv)  permit the Company to participate in any proceedings 
relating to such claim;

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provided, however, that the Company shall bear and pay directly all costs and
expenses (including additional interest and penalties) incurred in connection
with such contest and shall indemnify and hold the Executive harmless, on an
after-tax basis, for any Excise Tax or income tax (including interest and
penalties with respect thereto) imposed as a result of such representation and
payment of costs and expenses. Without limitation on the foregoing provisions of
this Section 8(c), the Company shall control all proceedings taken in connection
with such contest and, at its sole option, may pursue or forgo any and all
administrative appeals, proceedings, hearings and conferences with the taxing
authority in respect of such claim and may, at its sole option, either direct
the Executive to pay the tax claimed and sue for a refund or contest the claim
in any permissible manner, and the Executive agrees to prosecute such contest to
a determination before any administrative tribunal, in a court of initial
jurisdiction and in one or more appellate courts, as the Company shall
determine; provided, however, that if the Company directs the Executive to pay
such claim and sue for a refund, the Company shall advance the amount of such
payment to the Executive, on an interest-free basis and shall indemnify and hold
the Executive harmless, on an after-tax basis, from any Excise Tax or income tax
(including interest or penalties with respect thereto) imposed with respect to
such advance or with respect to any imputed income with respect to such advance;
and further provided that any extension of the statute of limitations relating
to payment of taxes for the taxable year of the Executive with respect to which
such contested amount is claimed to be due is limited solely to such contested
amount. Furthermore, the Company's control of the contest shall be limited to
issues with respect to which a Gross-Up Payment would be payable hereunder and
the Executive shall be entitled to settle or contest, as the case may be, any
other issue raised by the Internal Revenue Service or any other taxing
authority.

         (d) If, after the receipt by the Executive of an amount advanced by the
Company pursuant to Section 8(c), the Executive becomes entitled to receive any
refund with respect to such claim, the Executive shall (subject to the Company's
complying with the requirements of Section 8(c)) promptly pay to the Company the
amount of such refund (together with any interest paid or credited thereon after
taxes applicable thereto). If, after the receipt by the Executive of an amount
advanced by the Company pursuant to Section 8(c), a determination is made that
the Executive shall not be entitled to any refund with respect to such claim and
the Company does not notify the Executive in writing of its intent to contest
such denial of refund prior to the expiration of 30 days after such
determination, then such advance shall be forgiven and shall not be required to
be repaid and the amount of such advance shall offset, to the extent thereof,
the amount of Gross-Up Payment required to be paid.

         9.  CONFIDENTIAL INFORMATION.  (a)  The Executive shall hold in a 
fiduciary capacity for the benefit of the Company all

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secret or confidential information, knowledge or data relating to the Company or
any of its affiliated companies, and their respective businesses, which shall
have been obtained by the Executive during the Executive's employment by the
Company or any of its affiliated companies and which shall not be or become
public knowledge (other than by acts by the Executive or representatives of the
Executive in violation of this Agreement). After termination of the Executive's
employment with the Company, the Executive shall not, without the prior written
consent of the Company or as may otherwise be required by law or legal process,
communicate or divulge any such information, knowledge or data to anyone other
than the Company and those designated by it. In no event shall an asserted
violation of the provisions of this Section 9 constitute a basis for deferring
or withholding any amounts otherwise payable to the Executive under this
Agreement.

         (b)  In the event of a breach or threatened breach of this Section 9,
the Executive agrees that the Company shall be entitled to injunctive relief in
a court of appropriate jurisdiction to remedy any such breach or threatened
breach, the Executive acknowledges that damages would be inadequate and
insufficient.

         (c)  Any termination of the Executive's employment or of this 
Agreement shall have no effect on the continuing operation of this Section 9.

         10.  SUCCESSORS.  (a)  This Agreement is personal to the Executive and
without the prior written consent of the Company shall not be assignable by the 
Executive otherwise than by will or the laws of descent and distribution.  This
Agreement shall inure to the benefit of and be enforceable by the Executive's
legal representatives.

         (b)  This Agreement shall inure to the benefit of and be binding upon 
the Company and its successors and assigns.

         (c)  The Company will require any successor (whether direct or 
indirect, by purchase, merger, consolidation or otherwise) to all or
substantially all of the business and/or assets of the Company to assume
expressly and agree to perform this Agreement in the same manner and to the
same extent that the Company would be required to perform it if no such
succession had taken place. As used in this Agreement, "Company" shall mean the
Company as hereinbefore defined and any successor to its business and/or assets
as aforesaid which assumes and agrees to perform this Agreement by operation of
law, or otherwise.

         11.  MISCELLANEOUS.  (a)  This Agreement shall be governed by and 
construed in accordance with the laws of the Commonwealth of Massachusetts, 
without reference to principles of conflict oflaws.  The captions of this 
Agreement are not part of the provisions hereof and shall have no force or 
effect.  This Agreement may not be amended or modified otherwise than by a

                                   - 12 -


<PAGE>   13


written agreement executed by the parties hereto or their respective successors
and legal representatives.

         (b)  All notices and other communications hereunder shall be in writing
and shall be given by hand delivery to the other party or by registered or
certified mail, return receipt requested, postage prepaid, addressed as follows:

         If to the Executive:             Donald L. Isaacs
         -------------------              34 Yarmouth Road
                                          Wellesley, MA  02181


         If to Bank of Boston:
         --------------------

                  100 Federal Street
                  Boston, Massachusetts 02110

                  Attention:  General Counsel

or to such other address as either party shall have furnished to the other in
writing in accordance herewith. Notice and communications shall be effective
when actually received by the addressee.

         (c)  The invalidity or unenforceability of any provision of this 
Agreement shall not affect the validity or enforceability of any other 
provision of this Agreement.

         (d)  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.

         (e)  The Executive's or the Company's failure to insist upon strict
compliance with any provision of this Agreement or the failure to assert any
right the Executive or the Company may have hereunder, including, without
limitation, the right of the Executive to terminate employment for Good Reason
pursuant to Section 4(c)(i)-(v) of this Agreement, shall not be deemed to be a
waiver of such provision or right or any other provision or right of this
Agreement.

         (f)  The Executive and the Company acknowledge that, except as may
otherwise be provided under any other written agreement between the Executive
and the Company, the employment of the Executive by the Company is "at will",
and prior to the Effective Date, the Executive's employment may be terminated by
either the Executive or the Company at any time, in which case the Executive
shall have no further rights under this Agreement. From and after the Effective
Date this Agreement shall supersede any other employment, severance or change of
control agreement between the parties with respect to the subject matter hereof,
including, without limitation, Executive's participation in the Company's Plan
Supplementing Statutory Insurance Pay.

                                   - 13 -


<PAGE>   14



                  IN WITNESS WHEREOF, the Executive has hereunto set the
Executive's hand and, pursuant to the authorization from its Board of Directors,
the Company has caused these presents to be executed in its name on its behalf,
all as of the day and year first above written.

                                           /s/ Donald L. Isaacs
                                     ----------------------------------
                                     DONALD L. ISAACS

                                     BANK OF BOSTON CORPORATION

                                     By    /s/ Peter J. Manning
                                        -------------------------------

                                     BAYBANKS, INC.

                                     By    /s/ William M. Crozier, Jr.
                                        -------------------------------

                                   - 14 -