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                                                     Exhibit (10)-20
                                                     Commonwealth Edison Company
                                                     Form 10-K File No. 1-1839



                          COMMONWEALTH EDISON COMPANY

                         RETIREMENT PLAN FOR DIRECTORS

                       As Amended Through March 12, 1997


                                  I.  Purpose
                                  -----------

          The Commonwealth Edison Company Retirement Plan for Directors is
hereby established by Commonwealth Edison Company ("Company") to provide
benefits for eligible members of the Company's Board of Directors as hereinafter
set forth.

                               II.  Definitions
                               ----------------

          The following words and phrases shall have the meanings set forth
below unless a different meaning is required by the context:

          (a) Board:  The Board of Directors of the Company.
          (b)  ComEd Service:  A Director's service on the Board.
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          (c) Company: Commonwealth Edison Company, a corporation organized and
existing under the laws of the State of Illinois, or its successor or 
successors.

          (d)  Concurrent Service: A Director's concurrent service on the Board
and as a member of the Board of Directors of Unicom Corporation.

          (e) Director: Any member of the Board on or after January 1, 1987 who
is an outside director and who never has been an officer or employee of the
Company or any of its subsidiaries.

          (f) Eligible Director: A Director who meets the eligibility
requirements for retirement benefits set forth in Article III.

          (g) Eligible Service: A Director's (1) ComEd Service for any period,
plus (2) Unicom Service, if any, for any period after September 1, 1994,
provided, however, that any period of Concurrent Service shall be counted only
once (and not double-counted as a period of ComEd Service and Unicom Service) in
determining Eligible Service.

          (h) Plan: The Commonwealth Edison Company Retirement Plan for
Directors, as it may be amended from time to time.

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          (i) Retainer: The amounts designated as annual retainer established
for members of the Board for their service as such prior to any reduction or
offset therefrom as a result of Unicom Service, whether payable in cash or
shares of stock; provided, however, that the supplemental annual fee adopted by
the Board on May 22, 1996, to replace a previous annual grant of 300 shares of
Unicom Corporation common stock under the Unicom Corporation Outside Director
Stock Award Plan shall not be deemed to be "Retainer" for purposes of this
Plan."

          (j) Termination Date: The date on which an Eligible Director is no
longer a Director or a director of Unicom Corporation.

          (k) Unicom Plan: The Unicom Corporation Retirement Plan for Directors,
as it may be amended from time to time.

          (l) Unicom Service: A Director's service as a member of the Board of
Directors of Unicom Corporation.

                   III.  Eligibility For Retirement Benefits
                   -----------------------------------------

          Eligibility for retirement benefits under the Plan shall be limited to
each Director who has attained at least age 65 and who thereafter, for reasons
other than death, terminates

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ComEd Service while in good standing, provided that such Director shall have
completed at least five full years of Eligible Service or at least three full
years of Eligible Service if such Director's Eligible Service commenced after
attaining age 65.

                       IV.  Amount of Retirement Benefit
                       ---------------------------------

          Each Eligible Director shall be entitled to an annual retirement
benefit, for the period provided in Article V, which shall be an amount equal to
the product of (a) the Retainer as in effect when such Eligible Director's
benefit payments commence, adjusted from time to time for any changes thereafter
in the Retainer, multiplied by (b) a fraction, the numerator of which shall be
the number of years of ComEd Service and the denominator of which shall be the
number of years of Eligible Service; provided, however, that in computing ComEd
Service, there shall be excluded one-half of the years of Concurrent Service;
and provided further, that in computing the number of years of ComEd Service,
Eligible Service and Concurrent Service for the purpose of this Article IV,
fractional years will be rounded up to the next higher whole year. Such benefit
shall be paid as hereinafter provided.

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                      V.  Payment of Retirement Benefits
                      ----------------------------------

          Retirement benefit payments shall commence to be paid to an Eligible
Director on the last day of the calendar quarter next following the Eligible
Director's Termination Date. Subsequent benefit payments shall be made on the
last day of each calendar quarter thereafter and shall be paid for a period
equal to the Eligible Director's years of Eligible Service. For the purpose of
determining the payment period, fractional years of Eligible Service will be
rounded up to the next higher whole year. Each installment of retirement benefit
payments shall be equal to one-fourth of the amount determined as provided in
Article IV hereof.

          In the event of the Eligible Director's death after his or her
Termination Date but before commencement of payments hereunder or before the
Eligible Director has received all payments to which the Eligible Director is
entitled hereunder, the benefit payments to which the Eligible Director would
have been entitled had the Eligible Director lived shall be paid in the same
amount to the Eligible Director's surviving spouse, if any, using the same
payment schedule and amount as would have applied if the Eligible Director had
lived. If there is no

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surviving spouse at the death of the Eligible Director or if a surviving spouse
dies before receiving any or all payments to which entitled under the Plan, the
Eligible Director's benefits under the Plan shall terminate.

          Notwithstanding the foregoing, by March 31, 1997 each Director may
irrevocably elect, in lieu of amounts otherwise payable pursuant to this Article
a lump sum amount, payable on the Eligible Director's Termination Date, or as
soon as practicable thereafter, either (a) by delivery of the number of whole
shares of common stock of Unicom Corporation ("Unicom Stock") to be received
with cash in lieu of fractional shares, or (b) in cash.

          The number of shares to be delivered pursuant to an election described
in clause (a) above shall be determined as follows: An equivalent number of
shares shall be calculated by using the lump sum present value on January 1,
1997 of the benefit otherwise payable pursuant to this Article divided by the
closing price of a share of Unicom Stock reported on the New York Stock Exchange
Composite Transactions on March 28, 1997, including for this purpose fractional
shares. The number of equivalent shares so determined shall be credited to an
account maintained by the Company on its books. As of each date (prior

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to the Eligible Director's Termination Date) on which a cash dividend is paid on
Unicom Stock, each such account shall be credited with an additional number of
equivalent shares to be determined by assuming reinvestment of equivalent
dividends on shares then in the account.

          The cash amount to be paid pursuant to an election under clause (b)
above shall be the lump sum present value on January 1, 1997, of the benefit
otherwise payable pursuant to this Article, determined by crediting such amount
to an account maintained by the Company on its books, increased by amounts
representing interest, compounded quarterly, at a rate equal to the stated
interest rate on the then most recently issued straight debt obligation of
Commonwealth Edison Company with a maturity of at least 3 years, and computed to
the date of payment.

          The lump sum present value of a benefit otherwise payable under the
Article as of January 1, 1997 shall be computed by the Company using the
discount rate then in use for purposes of determining the funding requirements
for the Commonwealth Edison Company Service Annuity System.

          If a Director does not make the election at the time specified in the
fourth preceding paragraph, his or her benefits

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shall be paid in the manner prescribed by the first two paragraphs of this
Article.

          In the event of death before retirement of a Director who has elected
payment of a lump sum amount in lieu of quarterly benefit payments otherwise
payable hereunder, such Director's surviving spouse, if any, shall receive a
lump sum payment in accordance with such Director's election, if such surviving
spouse would have been entitled to Pre-Retirement Death Benefits under Article
VI of this Plan but for the Director's election to take a lump sum amount. Such
lump sum payment shall be in the amount accrued in the Director's account on the
Company's books on the date of death and shall be payable to the surviving
spouse as soon as practicable thereafter. If such Director has no spouse or no
surviving spouse who would otherwise be entitled to Pre-Retirement Death
Benefits under Article VI, no lump sum payment shall be made.

          In the event the Eligible Service of a Director, who has elected a
lump sum amount in lieu of quarterly benefit payments hereunder, is terminated
due to disability, a lump sum payment shall be made to the Director (or to such
other person as may be determined in accordance with Article X of this Plan if
the Director is under legal disability or is otherwise unable

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properly to manage his or her affairs), if such Director qualifies for
Disability Benefits under Article VII of this Plan. Such lump sum payment shall
be made as soon as practicable following the determination of disability in
accordance with Article VII.

                      VI.  Pre-Retirement Death Benefits
                      ----------------------------------

          (a) If the Eligible Service of a Director who is eligible to retire as
an Eligible Director is terminated due to death, such Director's surviving
spouse, if any, shall receive the benefit to which the surviving spouse would
have been entitled had the Director retired and his Termination Date occurred on
the day prior to his or her death.

          (b) If the Eligible Service of a Director is terminated due to death
prior to attaining age 65 but after attaining age 62 and completing at least
five full years of Eligible Service, such Director's surviving spouse, if any,
shall receive the benefit to which the surviving spouse would have been entitled
had such Director attained age 65 and terminated Eligible Service on the day
prior to his or her death, except that (i) the amount of each installment of
such benefit shall be

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equal to one-fourth of the amount determined as provided in Article IV hereof
and (ii) the benefit shall be paid for a period equal to the Director's years of
Eligible Service at the Director's date of death.

          (c) Payments of any benefits under subparagraphs (a) or (b) shall
commence on the last day of the calendar quarter in which occurs the Director's
date of death. If the Director under subparagraphs (a) or (b) leaves no
surviving spouse, or if a surviving spouse dies before receiving any or all
payments to which entitled under the Plan, the Director's benefits under the
Plan shall terminate.

                           VII.  Disability Benefits
                           -------------------------

          If the Eligible Service of a Director is terminated due to disability
prior to attaining age 65 but after attaining age 62, such Director shall be
entitled to payment of benefits, if any, under this Plan on the same basis as he
or she would have been if he or she had attained age 65 prior to such
termination. For purposes of this Article VII, disability shall mean a
disability that prevents the Director from performing any and every duty of a
member of the Board. The determination of the

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Compensation Committee of the Board as to whether a Director is terminated due
to disability shall be final and conclusive.

                         VIII.  Financing of Benefits
                         ----------------------------

          The Plan shall be a noncontributory, nonqualified and unfunded plan.
Benefit payments under the Plan shall represent an unsecured general obligation
of the Company and shall be paid by the Company from its general assets. No
special fund or trust shall be created, nor shall any notes or securities be
issued with respect to any benefits under the Plan.

                          IX.  Forfeiture of Benefits
                          ---------------------------

          As long as a former Director is receiving or is entitled to receive
benefits under the Plan, such former Director will not directly or indirectly
enter into or in any manner take part in any business or other endeavor, either
as an employee, agent, independent contractor, owner or otherwise, which in any
manner competes or conflicts with the business of the Company or is detrimental
to the best interests of the Company, unless the Company gives its prior written
consent thereto. The failure of

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a former Director to comply with the provisions of this Article shall result in
the forfeiture of all further payments which otherwise would become due and
payable under the Plan to the former Director or to his or her surviving spouse.
Before any such forfeiture, the Company shall mail notice to the former Director
that consideration is being given to forfeiture pursuant to this Article. On
written request of the former Director within sixty days following the mailing
by the Company of the notice, the Compensation Committee of the Board shall
afford the former Director an opportunity, at any mutually convenient time
within that sixty-day period, to demonstrate to the Compensation Committee that
forfeiture of payments would not be justified.

                            X.  Facility of Payment
                            -----------------------

          Whenever a person entitled to receive any payment under the Plan is a
person under legal disability or a person not adjudicated incompetent but who,
by reason of illness or mental or physical disability, is in the opinion of the
Compensation Committee of the Board unable properly to manage his or her
affairs, then such payments shall be paid in such of the following ways as the
Compensation Committee deems best: (a) to

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such person directly; (b) to the legally appointed guardian or conservator of
such person; (c) to some relative or friend of such person for his or her
benefit; or (d) for the benefit of such person in such manner as the
Compensation Committee considers advisable. Any payment made in accordance with
the provisions of this Article shall be a complete discharge of any liability
for the making of such payment under the Plan, and the distributee's receipt
shall be a sufficient discharge of the Company.

                              XI.  Administration
                              -------------------

          The Plan shall be administered by the Compensation Committee of the
Board, which shall have full and final authority to interpret the provisions of
the Plan and to make determinations regarding the administration of the Plan.
All decisions and determinations by the Compensation Committee shall be final
and binding upon all parties.

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                              XII.  Miscellaneous
                              -------------------

          The Plan shall not affect in any way the rights of a Director under
any deferred compensation agreement between the Director and the Company.

          The Plan may not be cancelled by the Company upon any merger or
consolidation with or acquisition of the Company by any other entity, but shall
be binding upon and inure to the benefit of the successors and assigns of the
Company and the heirs, executors, administrators and assigns of each Director.

          No person shall have any right to commute, incumber, pledge or dispose
of any right to receive payments hereunder, nor shall such payments be subject
to seizure, attachment or garnishment for the payments of any debts, judgments,
alimony or separate maintenance obligations or be transferable by operation of
law in the event of bankruptcy, insolvency or otherwise, all payments and rights
hereunder being expressly declared to be nonassignable and nontransferable.

          The Plan may be amended from time to time or terminated by the Board
at any time, but no amendment or termination may adversely affect the rights of
any person then receiving benefits

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under the Plan or who is entitled to receive benefits under the Plan on account
of a Director's prior termination of Eligible Service.

          This Plan shall be governed by the law of the State of Illinois.

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