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                                                                   EXHIBIT 10.10


                            PEROT SYSTEMS CORPORATION
                             1991 STOCK OPTION PLAN

                    AMENDED AND RESTATED AS OF MARCH 23, 2000



         This 1991 Stock Option Plan, as amended and restated as of March 23,
2000, of Perot Systems Corporation is for the purpose of attracting and
retaining outstanding employees of the Company (defined below) and providing
them with a strong incentive to contribute to the success of the Company by
granting them options to acquire shares of Common Stock, $0.01 par value, of
Perot Systems in accordance with the provisions of the Plan, as set forth below.

         Certain capitalized terms used in this Plan are defined at the end of
the Plan. Other terms used in the Plan are defined in the text as they occur and
have the meanings there indicated.

1. Term and Amendments.

         The Plan is effective when approved by the Board of Directors of Perot
Systems. Either the Board of Directors or the shareholders may amend or
terminate the Plan in their sole discretion. Neither the Board of Directors nor
the shareholders, however, may amend or terminate the Plan in a way that
adversely affects any rights relating to stock options granted under the Plan
before the amendment or termination without the consent of the person whose
rights are adversely affected.

2. Administration.

         The Board of Directors is responsible for administering and
interpreting the Plan, which responsibility may be delegated to a Committee of
the Board or to the Chief Executive Officer or other officer of Perot Systems
(collectively, the "Committee"). The Committee may from time to time adopt,
amend, waive, and rescind such procedures for the administration of the Plan as
it deems advisable, consistent with the provisions of the Plan. To the extent
permitted by law, any determination made by the Committee in administering or
interpreting the Plan is conclusive.

3. Available Shares.

         The Board of Directors shall reserve for issuance not more than 109
million shares of Common Stock to be available for issue pursuant to stock
options granted under the Plan and stock options and restricted shares of Common
Stock issued under the Company's Restricted Stock Plan, 1996 Advisor and
Consultant Stock Option/Restricted Stock Incentive Plan, 1996 Non-Employee
Director Stock Option/Restricted Stock Incentive Plan, and Advisor Stock
Option/Restricted Stock Incentive Plan. Shares made available upon the exercise
of stock options granted under the Plan may be either treasury shares or
authorized but unissued shares or a combination of the two. If any stock option
granted under this Plan expires or becomes unexercisable without having been
exercised in full, the unpurchased shares of Common Stock that were subject to
such stock option shall become available for future grant or sale under this
Plan (unless the Plan has terminated), provided, however, that shares of Common
Stock that have


1991 Stock Option Plan
Amended and Restated as of March 23, 2000

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actually been issued under the Plan shall not be returned to the Plan and shall
not become available for future distribution under the Plan, except that if such
shares are repurchased by Perot Systems at their original purchase price, such
shares shall become available for future grant under the Plan. If any change is
made in the shares of Common Stock (including, but not limited to, by stock
dividend, stock split, or merger or consolidation, but not including the
issuance of additional shares for consideration), the Board of Directors or the
Committee, as appropriate, will make such adjustments in the number and kind of
shares (which may consist of shares of a surviving corporation to a merger) that
may thereafter be optioned and sold under the Plan and the number and kind of
shares (which may consist of shares of a surviving corporation to a merger) and
purchase price per share of shares subject to outstanding Stock Option
Agreements under the Plan as the Board of Directors or the Committee determines
are equitable to preserve the respective rights of the Participants in the Plan.

4. Participants; Stock Option Agreements.

         The Committee shall select the employees of the Company who will be
granted stock options under the Plan and shall determine the terms of the stock
options to be granted to each selected employee, including (i) the number of
shares of Common Stock to be covered by each option; (ii) the purchase price per
share of the Common Stock (consistent with applicable law) covered by each
option, which must be at least equal to the Market Value of the Common Stock at
the time of the grant or, in the case of grants after July 17, 1998, at a future
time selected by the Committee; (iii) the term of each option, which may not
exceed 11 years; (iv) the vesting schedule for each option; (v) any holding
period or other restriction applicable to shares of Common Stock purchased
pursuant to each option; and (vi) any other terms deemed appropriate by the
Committee. Each such employee may elect to become a Participant in the Plan by
entering into a Stock Option Agreement approved by the Committee. The Committee
and the Participant may thereafter amend, modify, or waive the provisions of the
Stock Option Agreement by mutual written agreement. The Stock Option Agreement
will contain provisions to reflect and enforce the applicable provisions of the
Plan and any other provisions deemed appropriate by the Committee, including the
following:

                  (a) Payment of Purchase Price Upon Exercise.

                  Each Stock Option Agreement will provide that the purchase
         price of the shares as to which an option is exercised must be paid to
         Perot Systems at the time of exercise either in cash or in such other
         consideration as the Committee may approve having a total fair market
         value, as determined by the Committee, equal to the purchase price, or
         a combination of cash and such other consideration. Other consideration
         may include shares of Common Stock already held by a Participant or
         Common Stock withheld upon the exercise of the option, which will be
         accepted at Market Value.

                  (b) Investment Representation.

                  Each Stock Option Agreement will provide that, upon demand by
         the Committee, any person exercising a stock option under the Plan may
         be required to deliver to the Committee, at the time of any exercise of
         the option, a written representation that the

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Amended and Restated as of March 23, 2000

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         shares acquired upon the exercise are being acquired for investment and
         not for resale or with a view to distribution.

5. Payment of Taxes with Common Stock.

         The Committee may elect to assist Participants in satisfying an
obligation to pay or withhold taxes required as a result of the exercise of an
option by accepting shares of Common Stock at Market Value to satisfy the tax
obligation. The shares of Common Stock accepted may be either shares withheld
upon the exercise of an option or other shares already owned by the Participant.
In determining whether to approve acceptance of shares of Common Stock to
satisfy a tax obligation, the Committee may consider whether the shares proposed
to be accepted are subject to any holding period or other restrictions on
transfer and may waive or arrange for the waiver of any such restrictions.

6. Restrictions and Conditions Applicable to Stock Options and Purchased Stock.

         All stock options granted to a Participant pursuant to a Stock Option
Agreement and shares of Purchased Stock shall, except as otherwise provided in
the Stock Option Agreement, be subject to the following restrictions and
conditions:

                  (a) Non-transferability of Options.

                  No option granted under the Plan may be sold or otherwise
         transferred other than by will or by the laws of descent and
         distribution upon the Participant's death. During the lifetime of the
         Participant, the option is exercisable only by the Participant.

                  (b) Restricted Stock.

                  Unless Perot Systems otherwise agrees in writing, shares of
         Purchased Stock may not be sold or otherwise transferred, other than by
         will or under the laws of descent and distribution upon the
         Participant's death, until and unless (i) any holding period or other
         restriction on such a sale or other transfer specified in the Stock
         Option Agreement has expired, and (ii) Perot Systems has waived in
         writing any option to buy back such shares that it may have under the
         Stock Option Agreement.

                  (c) Buyback of Purchased Stock and Payback of Certain Profits.

                  Perot Systems will have the right to buy back from a
         Participant any Purchased Stock then owned by the Participant and the
         right to require a Participant to pay back to Perot Systems the amount
         of the Participant's Net Investment Proceeds with respect to shares of
         Purchased Stock that have been sold or otherwise transferred by the
         Participant in the circumstances and on the terms and conditions
         specified in the Participant's Stock Option Agreement.


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7. Stock Certificates; Rights as Shareholder.

         A Stock Option Agreement may provide that Perot Systems will retain for
safekeeping all certificates representing shares of Purchased Stock issued under
the agreement. Each such certificate may bear such legends as the Committee
determines are necessary or appropriate. Whether or not certificates
representing such shares have been issued or delivered, each Participant upon
purchasing such shares will have all the rights of a shareholder of Common
Stock, including voting, dividend, and distribution rights, with respect to all
shares of Purchased Stock owned by the Participant, except as may otherwise be
provided in the Participant's Stock Option Agreement. No Participant will have
any rights as a shareholder with respect to any shares of Common Stock subject
to options granted under the Plan before the date of issuance to the Participant
of shares upon the exercise of such options.

8. Compliance with Laws and Regulations.

         The Plan, the grant and exercise of options under the Plan, and the
obligation of Perot Systems to sell and deliver shares under such options, are
subject to all applicable federal and state laws, rules, and regulations and to
such approvals by any government or regulatory agency as may be required. Perot
Systems is permitted a reasonable delay in issuing any shares of Common Stock
pursuant to the exercise of options granted under the Plan in order to
accommodate compliance with such laws, rules, regulations, and approvals,
including (i) the listing of such stock on any registered national securities
exchange or approval for quotation in the National Association of Securities
Dealers Automated Quotation ("NASDAQ") system and (ii) the completion of any
registration or qualification of such shares under any federal or state law, or
any ruling or regulation of any governmental body that Perot Systems may, in its
sole discretion, determine to be necessary or advisable.

9. Severability.

         If any provision of the Plan is held invalid or unenforceable for any
reason, the validity and enforceability of all other provisions of the Plan will
not be affected.

10. Effect on Other Plans.

         The adoption of this Plan has no effect on awards made or to be made
under other equity incentive plans covering employees of Perot Systems or any of
its subsidiaries or any of their predecessors or subsidiaries.

11. Governing Law.

         The Plan shall be governed by and construed in accordance with the law
of the State of Texas, without regard to the choice of law rules in such law.

12. Definitions.

         As used in this Plan, the following terms have the meanings indicated:

         "Board of Directors" means the Board of Directors of Perot Systems.


1991 Stock Option Plan
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         "Committee" means the Committee established by the Board of Directors
under Section 2 of the Plan.

         "Common Stock" means the Class A Common Stock, $0.01 par value, of
Perot Systems.

         "Company" means Perot Systems and its direct or indirect subsidiaries
(i) in which Perot Systems owns a 40% or greater voting, equity or other
economic interest or (ii) the financial statements of which are consolidated
with the financial statements of Perot Systems.

         "Market Value" of a share of Common Stock on a given date means the
closing sale price for Common Stock, as determined in good faith by the Board of
Directors, on such date or, if no closing sale price is available for such date,
on the most recent prior date for which a closing sale price is available or, if
no closing sale price is available, the closing bid price, as so determined, on
such date or, if no closing bid price is available for such date, the closing
bid price on the most recent prior date for which a closing bid price is
available.

         "Net Investment Proceeds", with respect to any share of Purchased Stock
sold or otherwise transferred by a Participant or a Participant's successor in
interest, means the greater of the value of the gross proceeds received for such
share or the Market Value of such share on the date of sale or transfer less, in
either case, (i) the exercise price of the option for such share plus simple
interest on such amount at the rate of 8% per annum to the date of the sale or
transfer, (ii) reasonable and customary commissions paid for the sale or
transfer, and (iii) the verified amount of any income taxes paid or payable on
the sale or transfer.

         "Participant" means a person who has entered into a Stock Option
Agreement and the person's successors and permitted assigns.

         "Perot Systems" means Perot Systems Corporation.

         "Plan" means this Stock Option Plan, as it may be amended.

         "Purchased Stock" means outstanding Common Stock purchased pursuant to
options granted under the Plan.

         "Stock Option Agreement" means an agreement entered into by an employee
and Perot Systems under which the employee accepts options granted under the
Plan.



1991 Stock Option Plan
Amended and Restated as of March 23, 2000


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