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                                                                    EXHIBIT 10.1

                     AMENDMENT THREE TO THE FIRST AMENDED
                    UNIGRAPHICS SOLUTIONS INC. 401(K) PLAN

          WHEREAS, Unigraphics Solutions Inc. ("Company") previously adopted the
First Amended Unigraphics Solutions Inc. 401(k) Plan ("Plan"); and

          WHEREAS, the Company reserved the right to amend the Plan in Section
16.1 thereof and delegated such authority to the Compensation Committee of the
Board of Directors of the Company; and

          WHEREAS, effective as of December 31, 2000, the Company desires to
amend the Plan to provide for an additional contribution to the Plan by the
Company for fiscal year 2000;

          NOW, THEREFORE, effective December 31, 2000, the Plan is amended by
adding a new Section 4.5A as follows:

     4.5A Additional Employer Contributions for 2000.

          The Employer shall make a contribution to the Plan for the Plan Year
ended December 31, 2000, on behalf of each Employee described in Section 4.5A.1.
in an amount determined and allocated in accordance with Section 4.5A.2. Such
contributions shall be paid to the Trustee not later than the time prescribed by
law for filing the Employer's federal income tax return for the taxable year
with or within which such Plan Year ends, including any extensions thereof.

          4.5A.1 Eligibility.

                 Each individual who was an Employee on January 1, 2000 and
     continuously thereafter during the 2000 Plan Year including December 31,
     2000 or, if earlier, (i) the date the Employee retired (as defined below);
     (ii) the date of the Employee's death or (iii) the date the Employee became
     disabled within the meaning of Section 8.2, shall receive the contribution
     described in this Section 4.5A. In addition, an individual who (a)
     terminated employment prior to January 1, 2000, at a time when he or she
     was an Employee, (b) was reemployed by the Employer as an Employee during
     the 2000 Plan Year and was granted an adjusted service date by Employer,
     and (c) was continuously employed after the date of his or her reemployment
     during the 2000 Plan Year including December 31, 2000, shall receive the
     contribution described in this Section 4.5A.

                 For purposes of this Section 4.5A, an individual shall be
     considered to have retired if he or she terminated employment during the
     Plan Year on or after (i) attaining age 55 and (ii) completing at least
     fifteen (15) continuous years of service with the Employer or its
     predecessors (Electronic Data Systems Corporation ("EDS") or McDonnell-
     Douglas Corporation ("MDC")) immediately prior to termination of employment
     with the Employer.

          4.5A.2. Contribution.

                 With respect to an Employee described in Section 4.5A.1, the
     Employer shall contribute an amount equal to the sum of such Employee's
     Base Credit, Excess Credit, Transition Credit, and Mid-Career Credit, as
     applicable. Such contribution shall be contributed to such Employee's
     Matching Contribution Account; provided that, a Matching Contribution
     Account shall be established for an Employee who has not previously been
     credited with matching contributions under the Plan.

                 (1) Base Credit. The Base Credit of an Employee age 49 or under
          as of December 31, 2000, shall be an amount equal to:

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                       (a) a percentage calculated by adding the sum of his or
                 her age plus Years of Service (including for this purpose
                 service with MDC which was counted for benefit purposes under
                 the EDS Retirement Plan) as of such date and dividing such sum
                 by twenty-two (22), but in no event less than one and a half
                 percent (1.5% or .015), multiplied by

                       (b) the Employee's Compensation for the Plan Year.

          The Base Credit of an Employee age 50 or older as of December 31,
          2000, shall be an amount equal to:

                       (a) a percentage calculated by adding the sum of his or
                 her age plus Years of Service (including for this purpose
                 service with MDC which was counted for benefit purposes under
                 the EDS Retirement Plan) as of such date and dividing such sum
                 by sixteen (16), multiplied by

                       (b) the Employee's Compensation for the Plan Year.

                 (2) Excess Credit. An Employee's Excess Credit, if any, shall
          be an amount equal to:

                       (a) the lesser of (i) such Employee's Base Credit or (ii)
                 five percent (5%), multiplied by

                       (b) the Employee's Compensation for the Plan Year in
                 excess of the Social Security Wage Base.

                 Social Security Wage Base shall mean the maximum annual wage
                 base upon which Old-Age, Survivors, and Disability Insurance
                 taxes are based during the Plan Year.

                 (3) Conversion Credit. If an Employee was employed with EDS or
          the Company on July 1, 1998, had attained at least age 44 as of such
          date and was fully vested under the EDS Retirement Plan as of such
          date, such Employee's Conversion Credit shall be an amount equal to:

                       (a) the sum of the Employee's Base Credit plus his or her
                 Excess Credit, if any, multiplied by

                       (b) the applicable percentage determined under the
                 following chart based on such Employee's age as of July 1,
                 1998:

                  Age                             Applicable %
                  ---                             ------------

                  44                              10
                  45                              20
                  46 to 56                        50
                  57 and over                     70

                 (4) Mid-Career Credit. If an Employee's age as of his or her
          Date of Employment, as defined in the EDS Retirement Plan, was greater
          than thirty-five (35), such Employee shall receive a Mid-Career Credit
          equal to:

                       (a) a percentage calculated by subtracting thirty-five
                 (35) from his or her age as of his or her Date of Employment,
                 and dividing this number by sixteen (16), and multiplied by

                       (b) the Employee's Compensation for the Plan Year.

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