Exhibit 10.1



                            BOSTON EDISON COMPANY
                    SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN







SECTION 1.  PURPOSE

     The purpose of the Boston Edison Company Supplemental Executive
Retirement Plan (the "Plan") is to reward certain key executive employees
of Boston Edison Company (the "Employer") and its subsidiaries through
supplemental retirement payments.

SECTION 2.  ADMINISTRATION

     The Executive Personnel Committee of the Board of Directors of the
Employer (the "EPC") and the Retirement Committee appointed to administer the
Boston Edison Retirement Plan (the "RC") will be responsible under the Plan
for carrying out their respective administrative and other duties as set forth
in the Plan.  In addition, the EPC has the full discretionary power and
authority to interpret the plan, settle all disputes which may arise in
connection with the Plan, and establish any claims procedures required by the
Employee Retirement Income Security Act of 1974.  The decisions,
interpretations and determinations made by the EPC or the RC relating to the
Plan will be final and conclusive on all persons.

     The Employer agrees to indemnify and to defend to the fullest possible
extent permitted by law any member of the EPC and the RC (including any person
who formerly served as a member of the EPC or the RC) against all liabilities,
damages, costs and expenses (including attorneys' fees and amounts paid in
settlement of any claims approved by the Company) occasioned by any act or
omission to act in connection with the Plan.

SECTION 3.  PARTICIPANTS

     Participants in the Plan will be those key executive employees of the
Employer and its subsidiaries selected from time to time by the EPC to
participate in plan benefits.

SECTION 4.  BENEFITS

     (a)  Full Benefit.  Each Participant who attains his or her Full Benefit
Age (as hereinafter defined) while an employee of the Employer or its
subsidiaries may terminate employment on the first day of any month thereafter
and receive an annual benefit calculated as of his or her termination date,
expressed as a single life annuity, equal to the excess (if any) of (A) over
(B),

            where (A) is the excess of (i) 60% of his or her Highest Average
            Total Compensation (as hereinafter defined), over (ii) 50% of the
            Participant's Primary Social Security Benefit (as hereinafter
            defined), which excess is then multiplied by a fraction the
            numerator of which is his or her Full Years of Continuous Service
            (as hereinafter defined) at the time of his or her termination
            (which in no event shall exceed 20) and the denominator of which
            is 20; and

            where (B) is the sum of the benefits which the Participant would
            be entitled to receive at such time from the Boston Edison
            Retirement Plan (as from time to time amended) and the Boston
            Edison Company Excess Benefit Plan (as from time to time amended),
            expressed as a single life annuity.

     (b)  Reduced Benefit.  Each Participant who attains age 55 while an
employee of the Employer or its subsidiaries and who completes five Full Years
of Continuous Service may terminate employment on the first day of any month
thereafter (but prior to his Full Benefit Age) and receive a reduced annual
benefit calculated as of his or her termination date in the same manner as
described in Section 4(a) above for a full benefit, but reduced by an amount
equal to .41666% multiplied by the aggregate number of months between the date
his or her benefit commences and his or her Full Benefit Age.  A Participant
who has not attained age 55 or who has not completed five Full Years of
Continuous Service, but who has entered into a change in control agreement
with the Company and whose age plus the number of any additional years of
service credited to him under said change in control agreement for purposes of
the Plan is 50 or more, will be considered to have an accrued benefit under
the Plan for purposes of said change in control agreement, based upon his or
her number of Full Years of Continuous Service and calculated and reduced as
of his or her termination date in the same manner as described in the
preceding provision of this Section 4(b).

     (c)  Payments of Benefits.  The annual benefit payable to a Participant
under Section 4(a) or (b) above will be paid as a single life annuity, a
Spousal Joint and Survivor Annuity (as hereinafter defined) or a Lump Sum (as
hereinafter defined), as elected by the Participant in accordance with rules
and procedures established by the RC.

     (d)  Benefit Definitions.  For purposes of the Plan, the following terms
have the following meanings:

            (1)  Highest Average Total Compensation means the average of the
            Participant's Total Compensation (as hereinafter defined) for the
            36 consecutive months in which the Participant had the highest
            Total Compensation.

            (2)  Lump Sum means a single payment of actuarial equivalent value
            to a single life annuity (as determined by the RC with reference
            to such actuarial factors as it shall select from time to time).

            (3)  Full Benefit Age means, for each Participant, age 62 or such
            other age as the EPC may determine for a Participant.

            (4)  Primary Social Security Benefit means the "Primary Social
            Security Benefit,"  as defined under the Boston Edison Retirement
            Plan (as from time to time amended), as determined by the RC.

            (5)  Total Compensation means, for any calendar month, the
            Participant's base compensation and annual bonus payments paid to
            the Participant during such calendar month by the Employer, plus
            any amounts that would have been paid to the Participant during
            the calendar month by the Employer as base compensation or annual
            bonus but for a salary reduction agreement in effect during such
            month under the Boston Edison Company Deferred Compensation Plan,
            as from time to time amended, or pursuant to Sections 125 or
            401(k) of the Internal Revenue Code of 1986 as amended.

            (6)  Spousal Joint and Survivor Annuity means an annuity of
            actuarial equivalent value to a single life annuity (as determined
            by the RC with reference to such actuarial factors as it shall
            select from time to time), under which the Participant receives a
            reduced benefit during his or her lifetime, and following the
            Participant's death, 50% (or 66 2/3% or 100%, as elected by the
            Participant) of such reduced benefit is paid for the life of the
            person who was the Participant's spouse on the date benefits
            commenced to the Participant.

            (7)  Full Years of Continuous Service means, for each Participant,
            the number of full years of continuous service with the Employer
            and its affiliates, beginning with the date on which the
            individual becomes a Participant in the Plan, credited to the
            Participant for purposes of the Plan by the EPC, plus such other
            periods of service, if any, as the EPC shall determine.

SECTION 5.  PRE-RETIREMENT DEATH BENEFIT

     In the case of a Participant who dies after attaining age 55 and
completing five Full Years of Continuous Service, but prior to the
commencement of his or her benefits under Section 4 above, his or her
surviving spouse, if any, will be entitled to receive an annual benefit for
his or her lifetime equal to the benefit such spouse would have received if
the Participant has terminated and commenced receiving his or her benefit
under the Plan immediately prior to his or her death under the 50% Spousal
Joint and Survivor Annuity form.  In lieu of such annual death benefit, the
surviving spouse may elect to receive his or her benefit as a Lump Sum in
accordance with rules and procedures established by the RC.

SECTION 6.  NO PLAN ASSETS

     Except as herein provided, the Employer shall not be required to set
aside or segregate any assets of any kind to meet its obligations hereunder
and all benefits payable under the Plan will be paid from the general assets
of the Employer.  The Employer may, however, but is not required to, establish
a trust of which the Employer is treated as the owner under subpart E, part I,
subchapter J, chapter 1, subtitle A of the Internal Revenue Code of 1986, as
amended (a "grantor trust") and may deposit funds with the trustee of the
grantor trust sufficient to satisfy the benefits.

SECTION 7.  PARTICIPANT'S RIGHTS; NO ASSIGNMENT

     A Participant's rights to benefits under the Plan shall be no greater
than the rights of a general, unsecured creditor of the Employer, and shall
not be assignable or subject to alienation, anticipation, garnishment,
attachment, or any other legal process by his creditors.

SECTION 8.  NO CONTRACT OF EMPLOYMENT

     The Plan will not be deemed to constitute a contract of employment
between the Employer and any Participant, or to be consideration for the
employment of any Participant.

SECTION 9.  APPLICATION OF ERISA

     The Plan is intended to be "a plan which is unfunded and is maintained by
an employer primarily for the purpose of providing deferred compensation for a
select group of management or highly compensated employees" within the meaning
of sections 201(2), 301(a)(3) and 401(a)(1) of the Employee Retirement Income
Security Act of 1974, as amended, and shall be administered in a manner
consistent with that intent.

SECTION 10.  AMENDMENT OR TERMINATION

     This Plan may be amended or terminated at any time and in any respect by
the Employer or the EPC; provided, however, that no amendment shall adversely
effect the amount of a Participant's benefit without his or her consent.

SECTION 11.  GOVERNING LAW

     This Plan shall be governed by and construed under the laws of the
Commonwealth of Massachusetts, to the extent such laws are not preempted by
federal laws.

IN WITNESS WHEREOF, Boston Edison Company has caused this Plan to be
executed by its officer hereunto duly authorized this 24th day of June, 1997.


                                    BOSTON EDISON COMPANY



                                    By:  /s/ Thomas J. May
                                         -------------------------------
                                             Thomas J. May