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                                                    Exhibit (10)-12
                                                    Unicom Corporation
                                                    Form 10-K File No. 1-11375
                                                    Commonwealth Edison Company
                                                    Form 10-K File No. 1-1839 


                               UNICOM CORPORATION

                        DEFERRED COMPENSATION UNIT PLAN
                     (as amended through October 25, 1995)

          1.  Purposes.  The purposes of the Unicom Corporation Deferred
Compensation Unit Plan (the "Plan") are (i) to align the interests of the
Company's stockholders and recipients of awards under the Plan by linking a
portion of such recipients, compensation to the amount of cash dividends paid
with respect to the Company's Common Stock and (ii) to assure continuity of
efficient management, by providing for awards under the Plan, which may be
wholly or partly in lieu of salary increases, to such persons.

          2.  Definitions.  In addition to the other terms defined in this Plan,
the following terms shall have the following meanings for purposes of this Plan:

          "Committee" means the Compensation Committee of the Board of Directors
     of the Company.

          "Common Stock" means the Common Stock, without par value, of the
     Company.

          "Company" means Unicom Corporation, an Illinois corporation.

          "Current Compensation Unit" means an award entitling the recipient to
     receive, following the award and during the continued employment of the
     recipient by the Company or its subsidiaries, an amount in cash equal to,
     and payable on the payment dates of, the cash dividends such recipient
     would have received if on the day of the award one share of Common Stock
     had been issued to such recipient; provided, however, that no amounts shall
     be payable under such award in respect of non-cash dividends paid on the
     Common Stock.

          "Retirement Compensation Unit" means an award under Section 4(c) or
     4(f) of this Plan entitling the recipient to receive, following the award
     and continuing for the recipient's lifetime, an amount 
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     equal to, and payable on the payment dates of, the cash dividends such
     recipient would have received if on the day of the award one share of
     Common Stock had been issued to such recipient; provided, however: (a) no
     amount shall be payable under such award in respect of non-cash dividends
     paid on the Common Stock; (b) payments in respect of such Unit in any
     calendar year shall not in any event be

     (i)  less than the average amount of the payments per Current Compensation
          Unit during the five calendar years preceding the termination of
          employment which gave rise to the award of such Retirement
          Compensation Unit (provided that for purposes of this provision, the
          payments per Current Compensation Unit in the calendar years prior to
          January 1, 1995 shall be deemed to be as follows:  1994--$1.60, 1993--
          $1.60, 1992--$2.65, 1991--$3.00 and 1990-$3.00), or

     (ii) more than such average amount (or the amount of the payments per
          Current Compensation Unit in the calendar year preceding such
          termination, if greater), increased at the compound annual rate of two
          percent to the end of the calendar year of payment,

     provided that the foregoing clause (i) and (ii) limits shall not apply to
     any such Units issued pursuant to Section 4(f) of this Plan and, instead,
     any such Units shall have the limits, if any, applicable to the
     corresponding retirement compensation units for which they are exchanged or
     such other limits, if any, as may be established by the Committee; and (c)
     upon the death of a recipient of a Unit, leaving a spouse surviving,
     payments on account of such Unit shall continue to be made to the  spouse
     for the spouse's lifetime, but only if (i) such Unit had originated from
     the deceased's employment by the Company or its subsidiaries and (ii) the
     surviving spouse was married to such recipient when his or her period of
     service with the Company and all of its subsidiaries terminated.
    
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          "Units" means Current Compensation Units and Retirement Compensation
     Units.

          3.  Eligible Participants.  Participants in the Plan shall consist of
such key executive and managerial employees of the Company and its subsidiaries
as the Committee in its sole discretion may select from time to time consistent
with the next sentence of this Section 3.  The number of active officers and
employees to whom Current Compensation Units may be so awarded in any one
calendar year shall be limited to such number fixed by the Committee annually,
but shall be so limited that the Plan shall remain primarily for the purpose of
providing deferred compensation for a select group of management employees
within the meaning of the Employee Retirement Income Security Act of 1974, as
amended.

          4.  Awards.  (a) Subject to Section 4(b), the Committee shall, from
time to time, award Current Compensation Units, which may be wholly or partly in
lieu of salary increases, to eligible participants.  Such awards shall be
evidenced by a written notification to the recipient, which shall indicate the
number of Current Compensation Units so awarded.

          (b)  The total number of Current Compensation Units awarded in any
calendar year shall be limited so that the compensation payable thereon would
not exceed one-tenth of one percent of "consolidated net income on the Common
Stock of the Company" (as hereinafter defined) for the preceding calendar year.
To compute this limitation, the "compensation payable thereon" shall be deemed
to be the amount which would have been paid in the preceding calendar year
either (a) on an equivalent number of units awarded on the record date for the
first cash dividend on the Common Stock paid in that year, or (b) at a rate per
unit equal to five percent of the book value per share of the Common Stock at
the end of that year, whichever results in the lower number of available units.
No Current Compensation Units shall be awarded in any calendar year if total
payments during the preceding calendar year on outstanding Units had reduced
consolidated net income on the Common Stock of the Company for such year by as
much as two percent.  As herein used, the term "consolidated net income on the
Common Stock of the Company" shall mean, for any calendar 
   
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year, such net income (after all Federal income and excess profits tax
provisions) of the Company and its consolidated subsidiaries, or of the Company
alone if there are no consolidated subsidiaries, as shown in the Annual Report
to the Stockholders of the Company for such year.

          (c)  Upon the termination of the employment by the Company and its
subsidiaries of a recipient of Current Compensation Units, such recipient's
Current Compensation Units shall automatically be converted into an equivalent
number of Retirement Compensation Units; provided, however, if such termination
of employment is due to the resignation of such recipient, then (i) such
recipient's Current Compensation Units, and any payments in respect thereof,
shall terminate immediately, and (ii) no Retirement Compensation Units shall be
awarded pursuant to this Section 4(c).  For purposes of the foregoing proviso, a
termination of employment resulting from a recipient's acceptance of a voluntary
separation offer made by the Company or its subsidiaries shall not be deemed a
resignation.

          (d)  If any recipient of Units should at any time engage in a
competitive business activity, such recipient's Units, and any payments in
respect thereof, shall terminate immediately.

          (e)  The number of outstanding Units shall be adjusted by the
Committee to reflect stock dividends, stock splits or other changes in the
Company's Common Stock.

          (f)  Notwithstanding the limitation contained in Section 4(b), the
Committee may, from time to time and in such manner and on such terms as it
shall consider to be appropriate, award Current Compensation Units and
Retirement Compensation Units under this Plan in exchange for outstanding
current compensation units and retirement compensation units, respectively,
under the Commonwealth Edison Company Deferred Compensation Plan.  Any Units so
issued shall not reduce the number of Current Compensation Units otherwise
issuable under Section 4(b).

          5.  Administration.  The Plan shall be administered and interpreted by
the Committee.  The Committee shall have the authority to adopt, alter and
repeal such administrative rules, 
    
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guidelines and practices governing the Plan and perform all acts, including the
delegation of its administrative responsibilities, as it shall, from time to
time, deem advisable; to construe and interpret the terms and provisions of the
Plan and any award issued under the Plan (and any notices relating thereto) and
to otherwise supervise the administration of the Plan. The Committee may correct
any defect, supply any omission or reconcile any inconsistency in the Plan or in
any notice of an award in the manner and to the extent it shall deem necessary
to carry the Plan into effect. Any decision, interpretation or other action made
or taken in good faith by or at the direction of the Committee (or any of its
members) arising out of or in connection with the Plan shall be within its
absolute discretion and shall be final, binding and conclusive on the Company
and all employees and participants and their respective beneficiaries, heirs,
executors, administrators, successors and assigns.

          Neither the Committee nor any member thereof shall be liable for any
act, omission, interpretation, construction or determination made in connection
with the Plan in good faith, and the members of the Committee shall be entitled
to indemnification and reimbursement by the Company in respect of any claim,
loss, damage or expense (including attorney's fees) arising therefrom to the
full extent permitted by law and under any directors, and officers' liability
insurance that may be in effect from time to time.  In addition, no member of
the Board and no employee of the Company shall be liable for any act or failure
to act hereunder, by any other member or employee or by any agent to whom duties
in connection with the administration of this Plan have been delegated or,
except in circumstances involving a member's or employee's bad faith, gross
negligence or fraud, for any act or failure to act by the member or employee.

          A majority of the Committee shall constitute a quorum, and the acts of
a majority of the members present at any meeting at which a quorum is present,
or acts approved in writing by a majority of the Committee without a meeting,
shall be the acts of the Committee.

          6.  Amendment and Termination.  The Board of Directors of the Company
shall have the right to modify or discontinue the Plan at any time, and to
establish a trust fund 
   
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to ensure the payment of benefits hereunder, provided that the rights of persons
entitled to payments on account of Units previously awarded shall in nowise be
thereby impaired.

          7.   Miscellany. (a)  Unless the Board of Directors takes necessary
action pursuant to Section 6 hereof, this Plan is intended to be unfunded.  With
respect to any payments as to which a participant has a fixed and vested
interest but which are not yet made to a participant by the Company, nothing
contained herein shall give any such participant any rights that are greater
than those of a general creditor of the Company.

          (b)  Neither this Plan nor the grant of any award hereunder shall give
any participant or other employee any right with respect to continuance of
employment by the Company or any of its subsidiaries, nor shall they be a
limitation in any way on the right of the Company or any subsidiary by which an
employee is employed to terminate his or her employment at any time.

          (c)  This Plan and actions taken in connection herewith shall be
governed and construed in accordance with the laws of the State of Illinois
(without regard to applicable Illinois principles of conflict of laws).
   
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