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                                                                   EXHIBIT 10.35


                                PROMISSORY NOTE


                                                                January 28, 1997
$187,500

FOR VALUE RECEIVED, TERRY M. ASHWILL ("Associate"), promises to pay to Perot
Systems Corporation, a Delaware corporation (the "Company"), or order, at the
principal offices of the Company or at such other place as the holder of this
Note may designate, the principal sum of $187,500 payable, along with interest
calculated at eight percent per annum (8%), on or before JANUARY 28, 2000, or
earlier if otherwise required pursuant to the terms of this Note. Interest,
unless required to be paid earlier pursuant to the terms of this Note, will be
payable annually, beginning JANUARY 28, 1998.

In order to facilitate the making of payments due on this Note, Associate
hereby requests the Company to make semi-monthly payroll deductions, each in
the amount of $625.00, from any amount owed to him on or about the 15th and the
last day of each month. The amounts so received will be debited against
interest due under this Note.

         The Company has the right to offset amounts due under this Note
against payroll payments to be made by the Company to Associate.

         This Note shall become immediately due and payable in full without
notice or demand upon the earlier of (i) termination of Associate's employment
with the Company or any subsidiary of the Company, for any reason, with or
without cause, or (ii) three months after the restrictions on transfer of
vested common stock set forth in Section 3(d) of the Restricted Stock Agreement
of even date herewith between Associate and Company lapse. In addition, if
Associate sells any of the Company common stock purchased in connection with
the issuance of this Note, Associate shall, within thirty days of such sale,
prepay this Note to the extent of the net proceeds of such sale, less any
income taxes payable by Associate with respect to income derived from such
sale.

         Payment of this Note is secured pursuant to a Pledge Agreement of even
date herewith between PSC and Associate (the "Pledge Agreement").

         Nothing in this Note shall confer upon Associate any right to continue
in the employ of the Company or any subsidiary of the Company or interfere in
any way with the right of the Company or any subsidiary of the Company to
terminate such employment at any time.

         Every amount overdue under this Note shall bear interest from and
after the date on which such amount first became overdue at an annual rate
(compounded annually) which is the lesser of (a) two percentage points above
the rate designated from time to time by NationsBank of Texas as its prime
lending rate or (b) the maximum amount permitted by law. Such interest on
overdue amounts under this Note shall be payable on demand and shall accrue
until the obligation of Associate with respect to the payment of such interest
has been discharged (whether before or after judgment).

         In no event shall any interest charged, collected or reserved under
this Note exceed the maximum rate then permitted by applicable law and if any
such payment is paid by Associate, then such excess sum shall be credited by
the holder as a payment of principal.

         All payments by Associate under this Note shall be made without
set-off or counterclaim and be free and clear and without any deduction or
withholding for any taxes or fees of any nature whatever, unless the obligation
to make such deduction or withholding is imposed by law.


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         Associate agrees to pay on demand all costs of collection, including
reasonable attorneys' fees, incurred by the holder in enforcing the obligations
of Associate under this Note.

         No delay or omission on the part of the holder in exercising any right
under this Note or the Pledge Agreement under which the Restricted Stock is
pledged shall operate as a waiver of such right or of any other right of such
holder, nor shall any delay, omission or waiver on any one occasion be deemed a
bar to or waiver of the same or any other right on any future occasion.
Associate hereby waives presentment, demand, protest and notices of every kind
and assents to any extension or postponement of the time of payment or any
other indulgence, to any substitution, exchange or release of collateral, and
to the addition or release of any other party or person primarily or
secondarily liable.

         This Note may be prepaid in whole or in part at any time or from time
to time in the sole discretion of the holder. Any such prepayment shall be
without premium or penalty.

         None of the terms or provisions of this Note may be waived, modified
or amended except by a written instrument duly executed on behalf of the holder
expressly referring to this Note and setting forth the provision so waived,
modified or amended.

         All rights and obligations hereunder shall be governed by the laws of
the State of Texas. Any action to enforce the provisions of, or otherwise
relating to, this Note may be brought in the appropriate courts in Dallas
County, Texas.

                                             /s/ TERRY M. ASHWILL
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                                             (Signature)

                                             Terry M. Ashwill
                                             ---------------------------------
                                             (Print Name of Associate)