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                                                                  Exhibit 10.24
                                                                  -------------

                           EMPLOYMENT AGREEMENT
                           --------------------

        AGREEMENT by and among Bank of Boston Corporation, a Massachusetts
corporation ("Bank of Boston" or the "Company"), BayBanks, Inc., a
Massachusetts corporation ("BayBanks") and Joan E. Tonra (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 the second anniversary thereof (the "Employment Period").  

        3.   TERMS OF EMPLOYMENT.  (a)  POSITION AND DUTIES.  (i) (A)  During
the Employment Period, the Executive shall serve in a position with the Company
or its affiliated companies commensurate with her position as Senior Vice
President and Controller of BayBanks immediately prior to the Effective Date
reporting to Mr. Vasily or his successor, with such 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 substantially all of her 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.  During the Employment Period it shall
not be a violation of this Agreement for the 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 Executives 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 

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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.

               (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 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.  

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               (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: 

               (i)  the continued failure of the Executive to perform 
substantially the Executives 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 

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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 or Good Reason.  For purposes of this Agreement, "Good Reasons" 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 Executives 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 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 Executives
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  




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Executives 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.  

          (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) two 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 BayBanks Supplemental 
Executive Retirement Plan as in effect immediately prior to the
Effective Date 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
Executive's employment continued for two years after the Date of Termination,
assuming for this purpose that (x) all accrued benefits are fully vested and
(y) the Executive's compensation during the two 


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years is that required by Section 3(b)(i) and her annual bonus in each of the 
three years is equal to the Eligible Annual Bonus; and 

               (iii)  for two years after the Executive's Date of Termination,
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 two years after
the Date of Termination 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 her 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 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 




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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 her 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) her 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 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 



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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 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.  


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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; 

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 


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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 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 he 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 


                                    -10-

<PAGE>   11

in accordance with the laws of the Commonwealth of Massachusetts,
without reference to principles of conflict of laws.  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
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:          Joan E.  Tonra
          -------------------           The Ledges, #81
                                        7 Wainwright Road
                                        Winchester, MA 01890

          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.  

                                    -11-
<PAGE>   12

        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/ Joan E. Tonra        
                              ---------------------------------
                                   Joan E. Tonra


                              BANK OF BOSTON


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

                              BAYBANKS, INC.


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


                        EMPLOYMENT AGREEMENT ADDENDUM
                        -----------------------------

I hereby acknowledge and confirm that for purposes of interpretation of
Section 3(a) of the Employment Agreement attached, the word "commensurate" does
not mean "equal" and should be understood in the context of the substantial
difference in size between Bank of Boston and BayBanks.  


                         Signed:   /s/ Joan E. Tonra        
                                --------------------------

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