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                                                                   Exhibit 10.16

                         AECOM TECHNOLOGY CORPORATION
               MANAGEMENT SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

                            Effective July 1, 1998
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                         AECOM TECHNOLOGY CORPORATION
               MANAGEMENT SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN


I.   Establishment and Purpose

     1.1  Effective July 1, 1998, AECOM Technology Corporation has established
          this Management Supplemental Executive Retirement Plan ("Plan") to
          supplement the retirement benefits payable to certain employees under
          the AECOM Pension Plan. This Plan is intended to be an unfunded plan
          maintained by the Company primarily for the purpose of providing
          deferred compensation for a select group of management or highly
          compensated employees described in Section 201(2) of ERISA.

II.  Definitions

     2.1  Actuarial Equivalent has the same meaning as under the AECOM Pension
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          Plan.

     2.2  AECOM Pension Plan means the AECOM Technology Corporation Pension
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          Plan, as amended from time to time.

     2.3  Beneficiary means the person(s) designated by the Participant in
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          writing to receive any death benefits payable under the AECOM Pension
          Plan.

     2.4  Board of Directors means the Board of Directors of the Company.
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     2.5  Code means the Internal Revenue Code of 1986, as amended from time to
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          time.

     2.6  Committee means the Pension Committee or such other committee
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          designated or appointed by the Board of Directors to administer the
          Plan.

     2.7  Company means AECOM Technology Corporation.
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     2.8  Disability has the same meaning as under the AECOM Pension Plan.
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     2.9  Early Retirement Date has the same meaning as under the AECOM Pension
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          Plan.

     2.10 Effective Date means July 1, 1998.
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     2.11 ERISA means the Employee Retirement Income Security Act of 1974, as
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          amended from time to time.

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     2.12 Normal Retirement Age has the same meaning as under the AECOM Pension
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          Plan.

     2.13 Participant refers to an employee of the Company who (a) is a member
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          of a select group of management or highly compensated employees
          (within the meaning of Section 201(2) of ERISA), (b) is an officer,
          (c) is eligible for the AECOM Technology Corporation Incentive
          Compensation Plan, and (d) has been selected by the Committee to
          participate in this Plan. The Committee shall maintain a record of
          Participants.

     2.14 Plan Administrator means the Committee.
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     2.15 Plan Year means the twelve-month period ending on September 30, with
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          the first Plan Year beginning July 1, 1998 and ending September 30,
          1998.

     2.16 Retirement Date means the first day of the month following a
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          Participant's termination of employment for any reason, including
          death.

     2.17 Spouse means the person to whom the Participant is married on his
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          Retirement Date or on his date of death, if earlier.

2.20      Total AECOM Pension Plan Benefit means the annual benefit the
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          Participant would have received under the AECOM Pension Plan if there
          was no amendment to the AECOM Pension Plan effective July 1,1998
          terminating participation for officers eligible for the AECOM
          Technology Corporation Incentive Compensation Plan;

     2.21 Year of Service means a year of Credited Service as defined in the
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          AECOM Pension Plan.


III. Benefits

     3.1  Plan Benefits
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          A Participant who terminates employment with the Company and who is
          entitled to a benefit under the AECOM Pension Plan shall be entitled
          to a benefit under this Plan commencing on the same date that his
          benefit under the AECOM Pension Plan commences. The amount of the
          benefit payable under this Plan shall be equal to (a) minus (b):

          (a) The Participant's Total AECOM Pension Plan Benefit;

          (b) The annual benefit payable to the Participant under the AECOM
              Pension Plan.

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     3.2  Rules Regarding Reductions
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          For purposes of calculating the amounts payable under the AECOM
          Pension Plan for purposes of Section 3.1, any portion of the
          Participant's benefits under the AECOM Pension Plan which is payable
          (or has been paid) to another person pursuant to a court order shall
          be treated as payable to the Participant.


     3.3  Form of Benefit
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          The Participant's benefit under Section 3.1 shall be paid in the same
          form as elected under the AECOM Pension Plan.


     3.4  Pre-Retirement Death Benefits
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          If the Participant dies while employed by the Company (whether or not
          before his Early Retirement Date), his surviving Spouse shall receive
          a monthly benefit for life equal to the amount that the Spouse would
          have received under the AECOM Pension Plan minus the amount received
          under the AECOM Pension Plan.



IV.  Amendment and Termination

     4.1  Amendment
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          The Board of Directors reserves the right in its discretion to amend
          this Plan at any time in whole or in part, provided, however, that no
          amendment shall result in the forfeiture of any Participant's Plan
          benefits earned prior to the date the Board adopts the amendment.  The
          Company shall notify Participants (and the Spouses of deceased
          Participants) of any amendments which affect the amount or timing of
          benefits within 90 days of the effective date of such amendments.

     4.2  Termination
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          The Board of Directors may terminate the Plan at any time.
          Termination shall not result in the forfeiture of any Participant's
          benefits earned prior to the date the Board adopts a resolution
          terminating the Plan.

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V.   Administration

     5.1  This Plan shall be adopted by the Company and shall be administered by
          the Committee.

     5.2  The Committee shall have the sole authority, in its discretion, to
          adopt, amend and rescind such rules and regulations as it deems
          advisable in the administration of the Plan, to construe and interpret
          the Plan, and the rules and regulations, and to make all other
          determinations and interpretations of the Plan.  All decisions,
          determinations, and interpretations of the Committee shall be final
          and binding on all persons, except as otherwise provided by law.
          Committee members who are Participants shall abstain from voting on
          any Plan matters that would cause them to be in constructive receipt
          of benefits under the Plan.  The Committee may delegate its
          responsibilities as it sees fit.

     5.3  If a Participant or Spouse believes benefits have been incorrectly
          calculated or denied, such person may file a claim with the Committee.
          The Committee shall follow the claims procedures in the AECOM Pension
          Plan.

     5.4  All Plan administrative expenses shall be paid by the Company.

     5.5  The Company shall indemnify the Committee and each Committee member
          against any and all claims, losses, damages, expenses (including
          reasonable counsel fees), and liability arising from any action,
          failure to act, or other conduct in the member's official capacity,
          except when due to the individual's own gross negligence or willful
          misconduct.


VI.  General Provisions

     6.1  No Funding Obligation. The amounts accrued by a Participant hereunder
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          are not held in a trust or escrow account and are not secured by any
          specific assets of the Company or in which the Company has an
          interest. This Plan shall not be construed to require the Company to
          fund any of the benefits provided hereunder nor to establish a trust
          for such purpose. The Company may make such arrangements as it desires
          to provide for the payment of benefits. Neither the Participant, the
          Spouse nor the Participant's estate shall have any rights against the
          Company with respect to any portion of the Participant's benefits
          except as a general unsecured creditor of the Company. No Participant
          has an interest in his benefits until the Participant actually
          receives payment.

     6.2  Non-alienation of Benefits.  No benefit under this Plan may be sold,
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          assigned, transferred, conveyed, hypothecated, encumbered,
          anticipated, or otherwise disposed of, and any attempt to do so shall
          be void.  No such benefit shall, prior to

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          receipt thereof by a Participant or Spouse, be in any manner subject
          to the debts, contracts, liabilities, engagements, or torts of such
          Participant.

     6.3  Limitation of Rights.  Nothing in this Plan shall be construed to
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          limit in any way the right of the Company to terminate a Participant's
          employment at any time for any reason whatsoever with or without
          cause; nor shall it be evidence of any agreement or understanding,
          express or implied, that the Company (a) will employ a Participant in
          any particular position, (b) will ensure participation in any
          incentive programs, or (c) will grant any awards from such programs.

     6.4  Applicable Law.  This Plan shall be construed and its provisions
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          enforced and administered in accordance with the laws of the State of
          California except as otherwise provided in ERISA.

This Plan is hereby adopted by the Company on this 1st day of July, 1998.


                         AECOM TECHNOLOGY CORPORATION

                         By  /s/ R. Keeffe Griffith
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                         Its        Vice President
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