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                                                                   EXHIBIT 10.12

                                      NSTAR

                            1997 SHARE INCENTIVE PLAN

1.  PURPOSE

     The purpose of this 1997 Share Incentive Plan (the "Plan") is to advance
the interests of NSTAR (the "Company") and its affiliates by enhancing their
ability (a) to attract and retain employees who are in a position to make
contributions to the success of the Company and its affiliates; (b) to reward
employees for such contributions; and (c) to encourage employees to take into
account the long-term interests of the Company and its affiliates through
ownership of common shares of, and other interests in the Company ("Common
Shares").

     The Plan is intended to accomplish these goals by enabling the Company to
grant awards ("Awards") to eligible employees.  Awards may be in the form of
Share Options (as described in Section 6), Shock Appreciation Rights (as
described in Section 7), Restricted Stock Awards (as described in Section 8),
Deferred Stock Awards (as described in Section 9), Performance Unit Awards (as
described in Section 10), Dividend Equivalent Awards (as described in Section
11), and Other Share-Based Awards (as described in Section 12).

2.  ADMINISTRATION

     The Plan will be administered by the Executive Personnel Committee of the
Board of Trustees of the Company, excluding any member who would not be (i) an
"outside director" for purposes of Section 162(m) of the Internal Revenue Code
of 1986, as amended (the "Code"), and the regulations thereunder, or (ii) a non-
employee director as defined in Rule 16b-3(b)(3) under the Securities Exchange
Act of 1934, as amended (the "Exchange Act") (the "Committee").  The Committee
will have full discretionary authority, not inconsistent with the express
provisions of the Plan, to administer the Plan in all respects, including
without limitation, authority (a) to grant Awards to such eligible employees as
the Committee may select ("Participants"); (b) to determine the type of Awards
to be granted and the times of grants; (c) to determine the number of Common
Shares to be covered by any Award; (d) to determine the terms and conditions of
any Award, which terms and conditions may differ among individual Awards and
Participants; (e) to prescribe the form or forms of instruments evidencing
Awards and any other instruments required under the Plan and to change such
forms from time to time; (f) to adopt, amend and rescind rules and regulations
for the administration of the Plan; (g) to interpret the Plan and to decide any
questions and settle all controversies and disputes that may arise in connection
with the Plan; and (h) to waive compliance by a Participant with any obligation
to be performed by him under an Award, except that the Committee may not, (i) in
the case of an incentive stock option (as described in Section 6), take any
action without consent of the Participant which would cause such option to lose
its status as an "incentive stock option" ("ISO") within the meaning of section
422 of the Code, or (ii) in the case of an Award intended to qualify as
"performance-based compensation"

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within the meaning of Section 162(m)(4)(C) of the Code, increase the amount of
compensation payable under the Award to the extent that such increase would
cause the Award to lose its qualification as such performance-based
compensation. Such determinations and actions of the Committee shall be
conclusive and shall bind all parties.

     The Committee may delegate to senior officers of the Company who are also
trustees of the Company (including, without limitation, the Chief Executive
Officer and/or President) its duties under the Plan subject to conditions and
limitations as the Committee may prescribe, except that only the Committee may
designate, and make grants of Awards to, Participants (i) who are subject to
Section 16 of the Exchange Act or any successor statute, including, without
limitation, decisions on timing, amount and pricing of Awards, or (ii) whose
compensation is covered by Section 162(m) of the Code.

3.  EFFECTIVE DATE AND TERM OF PLAN

     The Plan became effective on the date on which it was approved by the
stockholders of Boston Edison Company.  No Award may be granted under the Plan
after the completion of ten years from the date on which the Plan was adopted by
the Board of Directors of Boston Edison Company, but Awards previously granted
may extend beyond that date.

4.  SHARES SUBJECT TO THE PLAN

     (a)  Number of Shares.  Subject to adjustment as provided in Section 15,
the aggregate number of Common Shares that may be delivered under the Plan is
2,000,000, including shares issued in lieu of or upon reinvestment of dividends
arising from awards.  Common Shares may be issued up to this maximum pursuant to
any type or types of Awards, including ISOs.  For purposes of this limitation,
Awards and Common Shares which are forfeited or reacquired by the Company, and
Awards which are satisfied or otherwise terminated without the issuance of
Common Shares, will not be counted.

     (b)  Special Limitations Applicable to Certain Awards.  Subject to
adjustment as provided in Section 15 to the extent such adjustment is consistent
with the continued satisfaction by Awards of the requirements of Section
162(m)(4)(C) of the Code, (i) the maximum number of Common Shares for which
Options and SARs may be awarded under the Plan to any Participant in any
calendar year is in each case 100,000 shares, and (ii) the maximum number of
Common Shares with respect to which Restricted Stock Awards and Awards intended
to qualify as "performance-based compensation" under Section 162(m)(4)(C) of the
Code may be granted to any Participant in any calendar year is in each case the
equivalent of 25,000 shares.  For purposes of the preceding sentence, the
regrant of a canceled Option or SAR, or the repricing of an Option or SAR, shall
be treated as a separate Award to the extent required under Section 162(m)(4)(C)
of the Code.  The per-individual Award limitations described in this paragraph
are intended to enable certain Awards under the Plan to qualify for the
performance-based compensation exemption rules set forth under Section
162(m)(4)(C) of the Code and shall be subject to amendment or revision to the
extent (but only to the extent) consistent with such rules.

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     (c)  Shares to be Delivered.  Shares delivered under the Plan will be
authorized but unissued Common Shares or, if the Committee so decides in its
sole discretion, previously issued Common Shares acquired by the Company in the
open market or in private transactions, or Common Shares held in treasury.  No
fractional Common Shares will be delivered under the Plan.

5.  ELIGIBILITY

     Employees eligible to become Participants shall be those key employees of
the Company and its affiliates who, in the opinion of the Committee, are in a
position to make a contribution to the success of the Company or its affiliates.
Members of the Committee will not be eligible to become Participants.

6.  STOCK OPTIONS

     Stock Options granted under the Plan ("Options") may be either ISOs or non-
qualified stock options ("NSOs").  Except to the extent expressly designated as
an ISO (or to the extent it does not qualify as an ISO even if so designated),
each Option will be an NSO.

     No term of this Plan relating to ISOs will be interpreted, amended or
altered, nor will any discretion or authority granted to the Committee under the
Plan be exercised, so as to disqualify the Plan or, without the consent of the
optionee, any ISO, under Section 422 of the Code.  The documents evidencing ISOs
will contain such provisions as are required of ISOs under the applicable
provisions of the Code.

     Options granted under the Plan will be subject to the following terms and
conditions and will contain such additional terms and conditions, not
inconsistent with the terms of the Plan, as the Committee deems desirable:

     (a)  Exercise Price.  The exercise price of each Option will be determined
by the Committee, but may not be, in the case of an ISO, less than 100% (110%,
in the case of an ISO granted to a ten-percent shareholder) of the fair market
value per share of Common Shares at the time the Option is granted.  For this
purpose, "ten-percent shareholder" means any employee who at the time of grant
owns directly, or is deemed to own by reason of the attribution rules in section
424(d) of the Code, Common Shares possessing more than 10% of the total combined
voting power of all classes of shares of the Company or of any of its parent or
affiliates.

     (b)  Duration of Options.  An Option will be exercisable during such period
or periods as the Committee may specify.  The latest date on which an Option may
be exercised will be the date which is ten years (five years, in the case of an
ISO granted to a ten-percent shareholder) from the date the Option was granted
or such earlier date as may be specified by the Committee at the time the Option
is granted.

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     (c)  Exercise of Options.

          (1)  Options will be exercisable at such future time or times, whether
               or not in installments, as determined by the Committee at or
               after the grant date.  The Committee may at any time accelerate
               the exercisability of all or any portion of any Option.

          (2)  Any exercise of an Option must be by written notice to the
               Company, accompanied by (i) the document evidencing the Option
               (the "Option Certificate") and any other documents required by
               the Committee and (ii) payment in accordance with Section 6(d)
               below for the number of Common Shares for which the Option is
               exercised.

     (d)  Payment for and Delivery of Common Shares.  Common Shares purchased
upon exercise of an Option shall be paid for as follows:  (1) in cash or by
certified check, bank draft or money order payable to the order of the Company,
or (2) if so permitted by the Option Certificate or otherwise determined by the
Committee, (i) through the delivery of Common Shares (held for at least six
months, or such other period as the Committee may specify) having a fair market
value on the last business day preceding the date of exercise equal to the
purchase price, or (ii) by a combination of cash and Common Shares as provided
in clauses (1) and (2)(i) above, or (iii) by delivery of a promissory note of
the Participant to the Company, in the case of an ISO, payable on such terms as
are specified in the Option Certificate, and in the case of an NSO, payable on
such terms as are specified in the Option Certificate or as are otherwise
specified by the Committee, or by a combination of cash (or cash and Common
Shares) and the Participant's promissory note; provided, however, that if the
Common Shares are delivered upon exercise of the Option is an original issue of
authorized Common Shares, at least so much of the exercise price as represents
the par value of such Common Shares must be paid in cash if the Committee
determines that such cash payment is required by law.

     (e)  Nontransferability of Options.  Except as otherwise determined by the
Committee or specified in the Option Certificate, no Option may be transferred
other than by will or by the laws of descent and distribution, and during a
Participant's lifetime an Option may be exercised only by him or her.

     (f)  Death or Disability.  Except as otherwise determined by the Committee,
if a Participant's employment with the Company and its affiliates terminates by
reason of death or total and permanent disability, each Option held by the
Participant will become fully exercisable and will remain exercisable after the
date of such termination for a period of two years in the case of death and one
year in the case of total and permanent disability (but in no event later than
the date the option would have expired in all events under Section 6(b)). In the
case of a deceased Participant, such Option may be exercised within such time
limits by his executor or administrator, or by the person or persons to whom the
Option is transferred by will or the applicable laws of descent and
distribution.

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     (g)  Other Termination of Employment.  Except as otherwise determined by
the Committee, if a Participant's employment with the Company and its affiliates
terminates for any reason other than death or total and permanent disability,
all Options held by the Participant that are not then exercisable shall
terminate.  Options that are exercisable on the date of termination will
continue to be exercisable for a period of three months (but in no event later
than the date the option would have expired in all events under Section 6(b))
unless the employee has admitted to, or been convicted of, any act of fraud,
theft or dishonesty arising in the course of, or in connection with, his
employment with the Company and its affiliates, in which case the Option will
terminate immediately and in full, all except as otherwise determined by the
Committee.  Except as otherwise determined by the Committee, after completion of
that three-month period, such Options shall terminate to the extent not
previously exercised, expired or terminated.

7.  STOCK APPRECIATION RIGHTS

     (a)  Nature of Stock Appreciation Right.  A Stock Appreciation Right
("SAR") is an Award entitling the recipient to receive an amount in cash or
Common Shares or a combination thereof having a value equal to the excess of the
fair market value of a share of Common Shares on the date of exercise over the
fair market value of a share of Common Shares on the date of grant (or over the
Option exercise price, if the SAR was granted in tandem with an Option),
multiplied by the number of shares with respect to which the SAR has been
exercised, with the Committee having the right to determine the form of payment.

     (b)  Grant of SARs.  SARs may be granted in tandem with, or independently
of, Options granted under the Plan.  In the case of an SAR granted in tandem
with an NSO, such SAR may be granted either at or after the time of the grant of
such Option.  In the case of an SAR granted in tandem with an ISO, such SAR may
be granted only at the time of the grant of the Option.  SARs will be evidenced
by such written agreement as is deemed appropriate by the Committee.

     An SAR or applicable portion thereof granted in tandem with an Option will
terminate and no longer be exercisable upon the termination or exercise of such
Option, except that an SAR granted with respect to less than the full number of
shares covered by an Option will not be reduced until the exercise or
termination of the related Option exceeds the number of shares not covered by
the SAR.

     (c)  Terms and Conditions of SARs.  SARs will be subject to such terms and
conditions as are determined from time to time by the Committee, subject, in the
case of SARs granted in tandem with Options, to the following:

          (1)  SARs will be exercisable only at such time or times and to the
               extent that the related Option is exercisable.

          (2)  Upon the exercise of an SAR, the applicable portion of any
               related Option must be surrendered.

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          (3)  SARs will be transferable only with the related Option.  Except
               as otherwise determined by the Committee, all SARs will be
               exercisable during the Participant's lifetime only by the
               Participant or his legal representative.

          (4)  An SAR granted in tandem with an Option may be exercised only
               when the market price of the Common Shares subject to the Option
               exceeds the exercise price of such Option.

     The provisions of Sections 6(f) and 6(g) relating to the exercisability and
termination of Options shall also apply to SARs, whether or not granted in
tandem with Options.

     Any exercise of an SAR must be by written notice to the Company,
accompanied by the document evidencing the SAR and any other documents required
by the Committee.

     (d)  Discretionary Payments.  Notwithstanding that an Option at the time of
exercise shall not be accompanied by a related SAR, if the market price of the
shares subject to such Option exceeds the exercise price of such Option at the
time of its exercise, the Committee may, in its discretion, cancel such Option,
in which event the Company shall pay to the person exercising such Option an
amount equal to the difference between the fair market value of the Common
Shares to have been purchased pursuant to such exercise of such Option
(determined on the date the Option is canceled) and the aggregate consideration
to have been paid by such person upon such exercise.  Such payment shall be by
check or in Common Shares having a fair market value (determined on the date the
payment is to be made) equal to the amount of such payments or any combination
thereof, as determined by the Committee.  The Committee may exercise its
discretion under the first sentence of this paragraph (d) only in the event of a
written request of the person exercising the option, which request shall not be
binding on the Committee.

8.  RESTRICTED STOCK

     (a)  Nature of Restricted Stock Award.  A Restricted Stock Award
("Restricted Stock Award") is an Award entitling the recipient to acquire Common
Shares ("Restricted Stock") for a purchase price (which may be zero), subject to
such conditions, including the restrictions specified in Section 8(d) below, as
the Committee may impose at the time of grant.  The Committee may also condition
such acquisition on the attainment of specified performance goals as described
in Section 16(f) below.

     (b)  Restricted Stock Award Agreement.  A Participant who is granted a
Restricted Stock Award will have no rights with respect to such Award unless the
Participant accepts the Award within 60 days (or such shorter period as the
Committee may specify) following the Award date by making payment to the Company
by certified or bank check or other instrument acceptable to

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the Committee in an amount equal to the specified purchase price, if any, of the
shares covered by the Award and by executing and delivering to the Company an
agreement (a "Restricted Stock Award Agreement") in such form as the Committee
determines.

     (c)  Rights as a Shareholder.  Upon complying with Section 8(b) above, a
Participant will have all the rights of a shareholder with respect to the
Restricted Stock awarded to him including voting and dividend rights, subject to
the restrictions described in this Section 8 and subject to any other conditions
contained in the Restricted Stock Award Agreement.  Unless the Committee
otherwise determines, certificates evidencing shares of Restricted Stock will
remain in the possession of the Company until such shares are free of any
restrictions under the Plan.

     (d)  Restriction.  Except as otherwise determined by the Committee, shares
of Restricted Stock may not be sold, assigned, transferred, pledged or otherwise
encumbered or disposed of, except as specifically provided herein.  If a
Participant ceases for any reason to be employed by the Company or its
affiliates other than due to death or total and permanent disability, shares of
Restricted Stock held by such Participant shall be resold to the Company at
their purchase price, or forfeited to the Company if the purchase price was
zero, except as specifically set forth herein or otherwise determined by the
Committee.  Shares of Restricted Stock resold to the Company shall have the
status of authorized but unissued Common Shares.

          (1)  The Committee will specify in the Restricted Stock Award
               Agreement the date or dates (which may depend upon or be related
               to the attainment of performance goals and other conditions) on
               which the nontransferability of the Restricted Stock and the
               obligation of the Participant to resell such Stock to the Company
               will lapse.  The Committee may at any time accelerate such date
               or dates or waive such performance goals and other conditions.

          (2)  Unless otherwise determined by the Committee or specified in the
               Restricted Stock Award Agreement, if the Participant's employment
               terminates because of death or total and permanent disability,
               all restrictions on shares of Restricted Stock held by the
               Participant will lapse.

     (e)  Notice of Election.  Any Participant making an election under Section
83(b) of the Code with respect to a Restricted Stock Award must provide a copy
thereof to the Company within 30 days of the filing of such election with the
Internal Revenue Service.

     (f)  Dividends.  Dividends paid on shares of Restricted Stock shall be
either paid at the dividend payment date or deferred for payment to such date as
determined by the Committee, in cash or in unrestricted Common Shares having a
fair market value equal to the amount of such dividends.  Shares distributed in
connection with a stock split or dividend in shares of stock, and other property
distributed as a dividend, shall be subject to restrictions and a risk of
forfeiture to the same extent as the Restricted Stock with respect to which such
shares of Restricted Stock or other property has been distributed.

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9. DEFERRED STOCK AWARDS.

     (a)  Nature of Deferred Stock Award.  A Deferred Stock Award ("Deferred
Stock Award") is an award entitling the recipient to acquire Common Shares
("Deferred Stock") without payment in one or more installments at a future date
or dates, all as determined by the Committee.  The Committee may condition such
acquisition on the attainment of specified performance goals as described in
Section 16(f) below.

     (b)  Deferred Stock Award Agreement.  A Participant who is granted a
Deferred Stock Award shall have no rights with respect to such Award unless
within 60 days of the grant of such Award or such shorter period as the
Committee may specify, the Participant shall have accepted the Award by
executing and delivering to the Company an agreement (a "Deferred Stock Award
Agreement") in such form as the Committee determines.

     (c)  Restrictions on Transfer. Except as otherwise determined by the
Committee, Deferred Stock Awards and all rights with respect to such Awards may
not be sold, assigned, transferred, pledged, or otherwise encumbered, and shall
be exercisable during the Participant's lifetime only by the Participant or the
Participant's legal representative.

     (d)  Rights as a Shareholder.  A Participant receiving a Deferred Stock
Award will have rights of a shareholder only as to shares of Deferred Stock
actually received by the Participant under the Plan and not with respect to
shares subject to the Award but not actually received by the Participant. A
Participant shall be entitled to receive a share certificate for shares of
Deferred Stock only upon satisfaction of all conditions therefor specified in
the Deferred Stock Award Agreement.

     (e) Termination. Except as otherwise determined by the Committee, a
Participant's rights in all Deferred Stock Awards shall automatically terminate
upon the termination of such Participant's employment by the Company and its
affiliates for any reason (including death).

     (f)  Acceleration, Waiver, Etc.  At any time prior to the termination of a
Participant's employment, the Committee may in its discretion accelerate, waive,
or, subject to Section 16, amend any or all of the restrictions or conditions
imposed under any Deferred Stock Award.

     (g)  Payments in Respect of Deferred Stock.  Without limiting the right of
the Committee to specify different terms, the Deferred Stock Award Agreement may
either make no provisions for, or may require or permit the immediate payment,
deferral, or investment of amounts equal to, or less than, any cash dividends
which would have been payable on the Deferred Stock had such stock been
outstanding, all as determined by the Committee in its sole discretion.

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10.  PERFORMANCE UNIT AWARDS.

     (a)  Nature of Performance Units Awards.  A Performance Unit Award
("Performance Unit Award") is an award entitling the recipient to acquire cash
or Common Shares, or a combination of cash and Common Shares, upon the
attainment of specified performance goals as described in Section 16(f) below.
The Committee in its sole discretion shall determine whether and to whom
Performance Unit Awards shall be made, the performance goals applicable under
each such Award, the periods during which performance is to be measured and all
other limitations and conditions applicable to each such Award. Performance Unit
Awards may be awarded independent of or in connection with the granting of any
other Award under the Plan.

     (b)  Performance Unit Award Agreement.  A Participant shall have no rights
with respect to a Performance Unit Award unless within 60 days of the grant of
such Award or such shorter period as the Committee may specify, the Participant
shall have accepted the Award by executing and delivering to the Company a
Performance Unit Award Agreement.

     (c) Restrictions on Transfer. Except as otherwise determined by the
Committee, Performance Unit Awards and all rights with respect to such Awards
may not be sold, assigned, transferred, pledged, or otherwise encumbered, and if
exercisable over a specified period, shall be exercisable during the
Participant's lifetime only by the Participant or the Participant's legal
representative.

     (d)  Rights as a Shareholder.  A Participant receiving a Performance Unit
Award will have rights of a shareholder only as to Common Shares actually
received by the Participant under the Plan and not with respect to shares
subject to the Award but not actually received by the Participant. A Participant
shall be entitled to receive a stock certificate evidencing the acquisition of
Common Shares under a Performance Unit Award only upon satisfaction of all
conditions therefor specified in the Performance Unit Award Agreement.

     (e)  Termination. Except as otherwise determined by the Committee, a
Participant's rights in all Performance Unit Awards shall automatically
terminate upon the termination of such Participant's employment by the Company
and its affiliates for any reason (including death).

     (f)  Acceleration, Waiver, Etc.  At any time prior to the termination of a
Participant's employment, the Committee may in its discretion accelerate, waive,
or, subject to Section 16, amend any or all of the restrictions or conditions
imposed under any Performance Unit Award.

     (g)  Exercise.  The Committee in its sole discretion shall establish
procedures to be followed in exercising any Performance Unit Award, which
procedures shall be set forth in the Performance Unit Award Agreement.  The
Committee may at any time provide that payment under a Performance Unit Award
shall be made, upon satisfaction of the applicable performance goals, without
exercise by the Participant.  Except as otherwise specified by the Committee, a
Performance Unit granted in tandem with an Option may be exercised only while
the Option is exercisable, and the exercise of a Performance Unit granted in
tandem with any other Award shall reduce the number of shares subject to the
related award on such basis as is specified in the Performance Unit Award
Agreement.

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11.  DIVIDEND EQUIVALENT AWARDS.

     (a)  Nature of Dividend Equivalent Awards.  A Dividend Equivalent Award
("Dividend Equivalent Award") is an Award entitling the Participant to receive
cash, Common Shares, or other property equal in value to dividends paid with
respect to a specified number of Common Shares.  Dividend Equivalent Awards may
be awarded on a free-standing basis or in connection with another Award, and may
be paid currently or on a deferred basis.  The Committee may provide at the date
of grant or thereafter that the Dividend Equivalent Award shall be paid or
distributed when accrued or shall be deemed to have been reinvested in
additional Common Shares or such other investment vehicles as the Committee may
specify; provided, however, that Dividend Equivalent Awards (other than free-
standing Dividend Equivalent Awards) shall be subject to all conditions and
restrictions of the underlying Awards to which they relate.  The Committee may
also condition such Award on the attainment of specified performance goals as
described in Section 16(f) below.

     (b)  Dividend Equivalent Award Agreement.  A Participant who is granted a
Dividend Equivalent Award shall have no rights with respect to such Award unless
within 60 days of the grant of such Award or such shorter period as the
Committee may specify, the Participant shall have accepted the Award by
executing and delivering to the Company an agreement (a "Dividend Equivalent
Award Agreement") in such form as the Committee determines.

     (c)  Restrictions on Transfer. Except as otherwise determined by the
Committee, Dividend Equivalent Awards and all rights with respect to such Awards
may not be sold, assigned, transferred, pledged, or otherwise encumbered.

     (d)  Rights as a Shareholder.  A Participant receiving a Dividend
Equivalent Award will have rights of a shareholder only as to Common Shares
actually received by the Participant under the Plan and not with respect to
shares subject to the Award but not actually received by the Participant.

     (e)  Termination.  Except as otherwise determined by the Committee, a
Participant's rights in all Dividend Equivalent Awards shall automatically
terminate upon the termination of such Participant's employment by the Company
and its affiliates for any reason (including death).

     (f)  Acceleration, Waiver, Etc.  At any time prior to the Participant's
termination of employment, the Committee may in its discretion accelerate,
waive, or, subject to Section 16 of the Exchange Act, amend any or all of the
restrictions or conditions imposed under any Dividend Equivalent Award.

12.  OTHER STOCK-BASED AWARDS.

     (a)  Nature of Awards.  The Committee may grant other Awards under which
Common Shares are or may in the future be acquired ("Other Stock-Based Awards").
Such awards may

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include, without limitation, debt securities convertible into or exchangeable
for Common Shares upon such conditions, including attainment of performance
goals, as the Committee shall determine. Subject to the purchase price
limitations in paragraph (b) below, such convertible or exchangeable securities
may have such terms and conditions as the Committee may determine at the time of
grant. However, no convertible or exchangeable debt shall be issued unless the
Committee shall have provided (by Company right of repurchase, right to require
conversion or exchange, or other means deemed appropriate by the Committee) a
means of avoiding any right of the holders of such debt to prevent a Company
transaction by reason of covenants in such debt. The Committee may also
condition such Awards on the attainment of specified performance goals as
described in Section 16(f) below.

     (b)  Purchase Price; Form of Payment.  The Committee may determine the
consideration, if any, payable upon the issuance or exercise of an Other Stock-
Based Award.  The Committee may permit payment by certified check or bank check
or other instrument acceptable to the Committee or by surrender of other Common
Shares (excluding shares then subject to restrictions under the Plan).

     (c)  Forfeiture of Awards; Repurchase of Shares; Acceleration or Waiver of
Restrictions.  The Committee may determine the conditions under which an Other
Stock-Based Award shall be forfeited or, in the case of an Award involving a
payment by the recipient, the conditions under which the Company may or must
repurchase such Award or related Common Shares.  At any time the Committee may
in its sole discretion accelerate, waive, or, subject to Section 16 of the
Exchange Act, amend any or all of the limitations or conditions imposed under
any Other Stock-Based Award.

     (d)  Other Stock-Based Award Agreements.  A Participant shall have no
rights with respect to any Other Stock-Based Award unless within 60 days after
the grant of such Award (or such shorter period as the Committee may specify)
the Participant shall have accepted the Award by executing and delivering to the
Company an agreement (an "Other Stock-Based Award Agreement") in such form as
the Committee determines.

     (e)  Restrictions on Transfer.  Except as otherwise determined by the
Committee, Other Stock-Based Awards may not be sold, assigned, transferred,
pledged, or encumbered nor shall any Other Stock-Based Award be transferred
other than by will or by the laws of descent and distribution or be exercisable
during the Participant's lifetime by other than the Participant or the
Participant's legal representative.

     (f)  Rights as a Shareholder.  A recipient of any Other Stock-Based Award
will have rights of a shareholder only at the time and to the extent, if any,
specified in the Other Stock-Based Award Agreement or otherwise determined by
the Committee.

     (g)  Deemed Dividend Payments; Deferrals.  Without limiting the right of
the Committee to specify different terms, an Other Stock-Based Award Agreement
may require or permit the immediate payment, waiver, deferral, or investment of
dividends or deemed dividends payable or deemed payable on Common Shares subject
to the Award.

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13. SUPPLEMENTAL GRANTS

     (a) Loans.  The Company may in its sole discretion make a loan to the
recipient of an Award hereunder, either on or after the date of grant of such
Award.  Such loans may be made either in connection with the exercise of a Stock
Option, an SAR or an Other Stock-Based Award, in connection with the purchase of
shares under any Award, or in connection with the payment of any federal, state
and local income tax in respect of income recognized under any Award.  The
Committee shall have full authority to decide whether to make a loan hereunder
if it determines that the making of such loan is in the best interest of the
Company, and to determine the amount, term, and provisions of any such loan,
including the interest rate (which may be zero) charged in respect of any such
loan, whether the loan is to be secured or unsecured, the terms on which the
loan is to be repaid and the conditions, if any, under which it may be forgiven.
However, no loan hereunder shall provide or reimburse to the borrower the amount
used by him for the payment of the par value of any Common Shares issued, have a
term (including extensions) exceeding ten years in duration, or be in an amount
exceeding the total exercise or purchase price paid by the borrower under an
Award or for related Common Shares under the Plan plus an amount equal to the
cash payment permitted in the following paragraph.

     (b)  Cash Grants.  The Committee may at any time authorize a cash payment,
in respect of the grant or exercise of an Award under the Plan (or the lapse or
waiver of restrictions under an Award) which shall not exceed the amount which
would be required in order to pay in full any federal, state and local income
tax due as a result of income recognized by the recipient under both the Award
and such cash payment, in each case assuming that such income is taxed at the
regular maximum marginal rate applicable to individuals under the Code as in
effect at the time such income is includable in the recipient's income.  Subject
to the foregoing, the Committee shall have complete authority to decide whether
to make such cash payments in any case, to make provision for such payments
either simultaneously with or after the grant of the associated Award and to
determine the amount of each such payment.

14.  CHANGE OF CONTROL

     Notwithstanding any other provision of this Plan, in the event of a Change
of Control of the Company as defined in Exhibit A hereto (a) each outstanding
Award held by each Participant the exercisability of which is restricted or
limited will immediately become fully exercisable; and (b) restrictions and
conditions on each outstanding Award subject to such restrictions and conditions
held by each Participant will immediately lapse or be deemed waived.

15.  CHANGES IN COMPANY; SUBSTITUTE AWARDS

     (a)  Changes in Capital Stock.  In the event of a share dividend, share
split or combination of shares, recapitalization or other change in the
Company's capital shares, the number and kind of shares, securities of the
Company or other consideration issued or issuable in respect of Awards

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<PAGE>

then outstanding or subsequently granted under the Plan, the maximum number of
shares or securities that may be delivered under the Plan, the purchase price
and other relevant provisions will be appropriately adjusted by the Committee,
whose determination shall be binding on all persons.

     The Committee may also adjust the number of shares, securities or other
consideration issued or issuable in respect of outstanding Awards, the exercise
price of outstanding Awards and the other terms of outstanding Awards, and may
make adjustments in the terms and conditions of, and the criteria and
performance objectives included in, Awards, to take into consideration material
changes in accounting practices or principles, consolidations or mergers (except
those described in Section 15(b) below), acquisitions or dispositions of shares
or property or any other event if it is determined by the Committee that such
adjustment is appropriate to avoid distortion in the operation of the Plan.
Adjustments under this paragraph will be made only to the extent they are
consistent with the requirements for ISOs or under Section 162(m)(4)(C) of the
Code.

     (b)  Merger, Etc.  Subject to Section 14, in the event of a dissolution or
liquidation of the Company or a merger or consolidation in which the Company is
not the surviving corporation or its outstanding shares are converted into
securities of another corporation or exchanged for other consideration, all
Awards granted hereunder will terminate, but during a period commencing 20 days
prior to the effective date of any such dissolution or liquidation (or 20 days
prior to any earlier related sale of substantially all the assets of the
Company) or of any such merger or consolidation, subject to the effectiveness of
such dissolution, liquidation, sale, merger or consolidation (1) all Awards
outstanding hereunder the exercisability of which is restricted or limited will
become immediately exercisable, and (2) all restrictions and conditions on all
Awards subject to such restrictions and conditions will immediately lapse or be
deemed waived; provided, however, that, unless the event will give rise to a
Change of Control or it is anticipated that a Change of Control will coincide
with or follow the event, the Committee may instead arrange that the successor
or surviving corporation, if any, grant replacement or substitute Awards on
terms and conditions as the Committee considers appropriate in the
circumstances.

     (c)  Substitute Awards.  The Company may grant Awards under the Plan in
substitution for stock or share and stock based awards held by employees of
another corporation who concurrently become employees of the Company or its
affiliate as the result of a merger or consolidation of the employing
corporation with the Company or its affiliate or the acquisition by the Company
or a affiliate of property or stock of the employing corporation.  The Committee
may direct that the substitute Awards be granted on such terms and conditions as
the Committee considers appropriate.  The shares which may be delivered under
such substitute Awards will be in addition to the maximum number of shares
provided for in Section 4(a) only to the extent that the substitute Awards are
both (1) granted to persons whose relationship to the Company does not make (and
is not expected to make) them subject to Section 16(b) of the Exchange Act and
(2) are granted in substitution for awards issued under a plan approved, to the
extent then required under Rule 16b-3 (or any successor rule under the Exchange
Act), by the shareholders of the entity which issued such predecessor awards.

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<PAGE>

16.  GENERAL PROVISIONS

     (a)  No Distribution; Compliance with Legal Requirements, Etc.  The
Committee may require each person acquiring Common Shares pursuant to an Award
to represent to and agree with the Company in writing that such person is
acquiring the Common Shares without a view to distribution thereof.

     The Company will not be obligated to deliver any Common Shares pursuant to
an Award (1) until, in the opinion of the Company's counsel, all applicable
federal and state laws and regulations have been complied with, including, if
required, the receipt of all necessary approvals from the Massachusetts
Department of Telecommunications and Energy, and (2) if the outstanding Common
Shares is at the time listed on any stock exchange, until the shares to be
delivered have been listed or authorized to be listed on such exchange upon
official notice of issuance, and (3) until all other legal matters in connection
with the issuance and delivery of such shares have been approved by the
Company's counsel.  If the sale of Common Shares has not been registered under
the Securities Act of 1933, as amended, the Company may require such
representations or agreements as counsel for the Company may consider
appropriate to avoid violation of such Act and may require that the certificates
evidencing such Common Shares bear an appropriate legend restricting transfer.

     Notwithstanding any provision of the Plan, the Company will be under no
obligation to deliver Common Shares to an estate of a deceased Participant, or
to the person or persons to whom the Award has been transferred by the
Participant's will or the applicable laws of descent and distribution, until the
Company is satisfied as to the authority of such person or persons.

     (b)  Tax Withholding, Etc.  Each Participant will, no later than the date
as of which the value of an Award or of any Common Shares or other amounts
received hereunder first becomes includable in gross income for federal income
tax purposes, pay to the Company, or make arrangements satisfactory to the
Committee regarding payment of, all federal, state and local taxes required by
law to be withheld with respect to such income.  The Company and its affiliates
will, to the extent permitted by law, have the right to deduct any such taxes
from any payment of any kind otherwise due to the Participant.

     The Committee may provide, in respect of any transfer of Common Shares
under an Award, that if and to the extent withholding of any federal, state or
local tax is required, the Participant may elect in such manner as the Committee
prescribes, to have the Company hold back from the transfer Common Shares having
a value calculated to satisfy such withholding obligation, or to deliver to the
Company previously owned shares of equal value.  Notwithstanding the foregoing,
in the case of a Participant subject to the restrictions of Section 16(b) of the
Exchange Act no such election shall be effective unless made in compliance with
any applicable requirements of Rule 16b-3(e) or any successor rule under such
Act.

     (c)  Continuance of Employment.  For purposes of the Plan, employment of a
Participant will not be considered terminated (1) in the case of sick leave or
other bona fide leave of absence

                                       14
<PAGE>

approved for purposes of the Plan by the Committee, so long as the Participant's
right to re-employment is guaranteed either by statute or by contract, or (2) in
the case of a transfer to the employment of a corporation (or a parent or
affiliate corporation of such corporation) issuing or assuming an option in a
transaction to which section 424(a) of the Code would apply.

     (d)  Fair Market Value.  For purposes of the Plan, in general, "fair market
value" of a share of Common Shares on any date means the closing price on such
date as reflected in the New York Stock Exchange Composite Index.  If, however,
the Committee determines that a different meaning is in any circumstance
necessary in order to comply with applicable law, such different meaning will
apply in that circumstance.

     (e)  Employment Rights.  Neither the adoption of the Plan nor the grant of
Awards will confer upon any employee any right to continued employment with the
Company or any affiliate or affect in any way the right of the Company or any
affiliate to terminate the employment of an employee at any time.  Except as
specifically provided by the Committee in any particular case, the loss of
existing or potential profit in Awards granted under this Plan shall not
constitute an element of damages in the event of termination of the employment
of an employee even if the termination is in violation of an obligation of the
Company to the employee by contract or otherwise.

     (f)  Awards Subject to Performance Conditions.   The Committee may, at the
time any Award described in the Plan is granted, impose the condition (in
addition to any conditions specified or authorized in any other provisions of
the Plan), that performance goals must be met prior to the Participant's
realization of any vesting, payment or benefit under the Award.  Performance
goals may be related to personal performance, corporate performance,
departmental performance, or any other category of performance established by
the Committee.  The Committee will determine the performance goals, the period
or periods during which performance is to be measured, and all other terms and
conditions applicable to the Award.  If necessary in order to qualify an Award
for the performance based remuneration exception described in Section
162(m)(4)(C) of the Code and the regulations thereunder, the Committee shall in
writing preestablish one or more specific, objectively determinable performance
goal or goals (based solely on one or more qualified performance criteria) no
later than ninety (90) days after the commencement of the period to which the
performance relates (or in any such other time as is required to satisfy the
conditions of Section 162(m)(4)(C) of the Code and the regulations thereunder).
For purposes of the preceding sentence, a qualified performance criterion is any
of the following:  (i) earnings per share, (ii) individual performance
objectives, (iii) net income, (iv) proforma net income, (v) return on designated
assets, (vi) return on revenues, or (vii) satisfaction of Company-wide or
departmental based objectives.

17.  EFFECT, DISCONTINUANCE, CANCELLATION, AMENDMENT AND TERMINATION.

     Neither adoption of the Plan nor the grant of Awards to a Participant shall
affect the Company's right to grant to such Participant awards that are not
subject to the Plan, to issue Common

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<PAGE>

Shares to such Participant as a bonus or otherwise, or to adopt other plans or
arrangements under which Common Shares may be issued to employees.

     The Committee may at any time discontinue granting Awards under the Plan.
With the consent of the Participant, the Committee may at any time cancel an
existing Award in whole or in part and grant the Participant another Award for
such number of Common Shares as the Committee specifies, subject to Section
4(b).  The Committee may at any time or times amend the Plan or any outstanding
Award for the purpose of satisfying the requirements of any changes in
applicable laws or regulations or for any other purpose which may at the time be
permitted by law; and may at any time terminate the Plan as to any further
grants of Awards; provided, however, that (except to the extent expressly
required or permitted herein) no such amendment shall, without the approval of
the shareholders of the Company, (a) increase the maximum number of shares
available for delivery under the Plan, (b) change the group of employees
eligible to receive Awards under the Plan, (c) reduce the price at which ISOs
may be granted, (d) extend the time within which Awards may be granted, or (e)
amend the provisions of this Section 17, and no such amendment shall adversely
affect the rights of any Participant (without his consent) under any Award
previously granted.



As adopted by the Board of Directors of Boston Edison Company:  January 23, 1997
As approved by the Shareholders of Boston Edison Company:  May 15, 1997
As amended:  April 22, 1998
As amended:  June 30, 1999
Assumed by NSTAR effective:  August 28, 2000

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<PAGE>

                                                                      APPENDIX A

     Change of Control.  For the purposes of this Agreement, a "Change of
Control" shall mean:

     a.   The acquisition by any Person of ultimate beneficial ownership (within
          the meaning of Rule 13d-3 promulgated under the Exchange Act) of 30%
          or more of either (i) the then outstanding common shares (or shares of
          common stock) of Parent (the "Outstanding Parent Common Shares") or
          (ii) the combined voting power of the then outstanding voting
          securities of the Parent entitled to vote generally in the election of
          trustees (or directors) (the "Outstanding Parent Voting Securities");
          provided, however, that for purposes of this subsection (a), the
          following acquisitions shall not constitute a Change of Control: (i)
          any acquisition directly from the Parent, (ii) any acquisition by the
          Parent or any affiliate of Parent, (iii) any acquisition by any
          employee benefit plan (or related trust) sponsored or maintained by
          the Parent, the Company or any affiliate of Parent or (iv) any
          acquisition by any Person pursuant to a transaction which complies
          with clauses (i), (ii) and (iii) of subsection (c) of this Exhibit A;
          or

     b.   Individuals who, as of the date hereof, constitute the Board of
          Trustees of the Parent (the "Incumbent Board") cease for any reason to
          constitute at least a majority of such board; provided, however, that
          any individual becoming a trustee (or director) subsequent to the date
          hereof whose election, or nomination for election by the Parent's
          shareholders, was approved by a vote of at least a majority of the
          trustees (or directors) then comprising the Incumbent Board shall be
          considered as though such individual were a member of the Incumbent
          Board, but excluding, for this purpose, any such individual whose
          initial assumption of office occurs as a result of an actual or
          threatened election contest with respect to the election or removal of
          trustees (or directors) or other actual or threatened solicitation of
          proxies or consents by or on behalf of a Person other than such board;
          or

     c.   Consummation of a reorganization, merger or consolidation or sale or
          other disposition of all or substantially all of the assets of the
          Parent (a "Business Combination"), in each case, unless, following
          such Business Combination, (i) all or substantially all of the
          individuals and entities who were the beneficial owners, respectively,
          of the Outstanding Parent Common Shares and Outstanding Parent Voting
          Securities immediately prior to such Business Combination beneficially
          own, directly or indirectly, immediately following such Business
          Combination more than 50% of, respectively, the then outstanding
          common shares (or shares of common stock) and the combined voting
          power of the then outstanding voting securities entitled to vote
          generally in the election of trustees (or directors), as the case may
          be, of the entity resulting from such Business Combination (including,
          without limitation, a entity which as a result of such transaction
          owns the Parent or all or substantially all of the Parent's assets
          either directly or through one or more subsidiaries) in substantially
          the same proportions as their ownership, immediately prior to such
          Business Combination of the Outstanding Parent Common Shares and
          Outstanding Parent Voting Securities,

                                       17
<PAGE>

          as the case may be, (ii) no Person (excluding any entity resulting
          from such Business Combination or any employee benefit plan (or
          related trust) of the Parent or the Company or such entity resulting
          from such Business Combination) ultimately beneficially owns, directly
          or indirectly, 30% or more of, respectively, the then outstanding
          common shares or shares of common stock of the entity resulting from
          such Business Combination or the combined voting power of the then
          outstanding voting securities of such entity except to the extent that
          such ownership existed prior to the Business Combination and (iii) at
          least a majority of the members of the board of trustees (or board of
          directors) of the entity resulting from such Business Combination were
          members of the Incumbent Board at the time of the execution of the
          initial agreement, or of the action of the Board of Trustees of the
          Parent, providing for such Business Combination; or

     d.   Approval by the shareholders of the Parent of a complete liquidation
          or dissolution of the Parent.

     For purposes of this Appendix A, the term "Parent" shall mean NSTAR, or, if
any entity shall own, directly or indirectly through one or more subsidiaries,
more than 50% of the outstanding common shares of NSTAR, such entity.

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