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                                                                   Exhibit 10.23


                               CRS SIRRINE, INC.
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN



        THIS INSTRUMENT made as of June 30, 1988 by CRS Sirrine, Inc. (the
"Company").

                            W I T N E S S E T H :

        WHEREAS, the Company maintains the CRS Sirrine, Inc. Supplemental
Executive Retirement Plan, effective November 1, 1987 (the "Plan"); and

        WHEREAS, the Company reserved the right in Article VIII to amend the
Plan at any time by action of its Board of Directors; and

        WHEREAS, the Board of Directors adopted resolutions on June 30, 1988 to
amend the Plan's provisions regarding a Change of Control (as hereinafter
defined) and certain related provisions;

        NOW, THEREFORE, the Plan is hereby amended, effective as of June 30,
1988, as follows:

        1.     The definition of "Change of Control" in Article II of the Plan
is hereby amended to read as follows:

                "A 'Change of Control' shall be deemed to occur when and only
                when any of the following events first occurs:

                        (a)     any person becomes the beneficial owner,
                directly or indirectly, of securities of the Company
                representing 25 percent or more of the combined voting power of
                the Company's then outstanding voting securities; or

                        (b)     three or more directors, whose election or
                nomination for election is not approved by a majority of the
                Incumbent Board (as hereinafter defined), are elected within
                any single 24-month period to serve on the Board; or

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                        (c)     members of the Incumbent Board cease to
                constitute a majority of the Board without the approval of the
                remaining members of the Incumbent Board; or

                        (d)     any merger (other than a merger in which the
                Company is the survivor and there is no accompanying Change of
                Control under subsection (a), (b) or (c) of this definition),
                consolidation, liquidation or dissolution of the Company or the
                sale of all or substantially all of the assets of the Company.

                Notwithstanding the foregoing, a Change of Control shall not be
                deemed to occur pursuant to subsection (a) above (i) solely 
                because 25 percent or more of the combined voting power of the 
                Company's outstanding securities is acquired by one or more 
                employee benefit plans maintained by the Company or by any 
                other employer the majority interest in which is held, directly
                or indirectly, by the Company; (ii) with respect to a 
                Participant who elects by written notice to the Company before 
                any disposition by the Company of all or substantially all of
                the business and assets of the architectural, engineering and
                construction businesses of the Company (herein called
                "Services") that such disposition shall not constitute a Change
                of Control for the purposes of the Plan; or (iii) on account of
                a disposition by the Company of all or substantially all of the
                assets and business of Services in respect of any Participant
                whose duties and responsibilities are principally in relation
                to business and operations of the Company other than Services,
                as conclusively determined in its absolute discretion by the
                Administrative Committee. For purposes of this definition, the
                terms 'person' and 'beneficial owner' shall have the meanings
                set forth in sections 3(a) and 13(d) of the Securities Exchange
                Act of 1934, as amended, and in the regulations promulgated
                thereunder, as in effect on June 30, 1988; and the term
                'Incumbent Board' shall mean (i) the members of the Board on
                June 30, 1988, to the extent that they continue to serve as
                members of the Board, and (ii) any individual who




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        becomes a member of the Board after June 30, 1988, if his election 
        or nomination for election as a director was approved by a
        vote of at least three-quarters of the then Incumbent Board."

        2.     The proviso clause in the first sentence of the definition of
"Retirement" in Article II of the Plan, which begins "provided that on or after
the date on which a Change of Control occurs", is hereby amended in its
entirety to read as follows:

        "; provided that on or after the date on which a Change of Control 
        occurs, a termination by the Employer of a Participant's employment 
        shall be deemed to be for cause, for purposes of the Plan,
        only if the Participant's employment is terminated because (A) he has
        engaged in unlawful acts that violate laws of the United States or of
        any state thereof and that were intended to result in the substantial
        personal enrichment of the Participant at the Company's expense, or (B)
        he has engaged (except by reason of incapacity due to illness or
        injury) in a material willful violation of his responsibilities to the
        Company that results in a material injury to the Company."

        3.     Section 9.1(c) of the Plan is hereby amended to read as follows:

                "(c) Any Participant (i) whose employment is terminated by the
        Company within three years after a Change of Control except for cause
        (as defined in the proviso in the definition of Retirement above) or
        (ii) with respect to whom (A) Good Reason arises within three years
        after a Change of Control and (B) the Participant terminates his
        employment with the Company within the earlier of (i) six months after
        the Good Reason arises or (ii) three years after the Change of Control,
        shall receive, in a single lump-sum cash payment made within 30 days
        after the date on which his employment terminates, the Equivalent Value
        of a Supplemental Retirement Benefit that is determined based on an
        Applicable Percentage of 20 percent.





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                For purposes of Section 9.1(c), Equivalent Value shall be
                determined as if the Participant were entitled to a series of 
                payments under the Plan commencing on the date on which his 
                termination of employment occurred. For purposes of 
                Section 9.1(c), a Participant shall be deemed to have 'Good 
                Reason' for terminating employment with the Company only if one
                or more of the following occurs after a Change of Control:

                        (i)     a change in the Participant's status or
                position(s) with the Company that, in the Participant's
                reasonable judgment, represents a demotion from the
                Participant's status or position(s) in effect immediately prior
                to the Change of Control;

                        (ii)     the assignment to the Participant of any
                duties or responsibilities that, in the Participant's
                reasonable judgment, are inconsistent with the Participant's
                status or position(s) in effect immediately prior to the Change
                of Control;

                        (iii)     layoff or involuntary termination of the
                Participant's employment, except in connection with the
                termination of the Participant's employment for cause (as
                defined in the proviso in the definition of 'Retirement,'
                above) or as a result of the Participant's Retirement,
                Disability or death;

                        (iv)     a reduction by the Company in the
                Participant's total compensation (which shall be deemed, for
                this purpose, to be equal to the base salary that he earned for
                the year preceding the Change of Control plus the aggregate
                bonus that he would have earned for the current year under the
                same criteria that were in effect for such preceding year);

                        (v)     a material increase in the Participant's
                responsibilities or duties without a commensurate increase in
                total compensation;

                        (vi)     the failure by the Company to continue in
                effect any Benefit Plan (as defined below) in which the
                Participant is




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                participating immediately prior to the Change of Control 
                (or plans or arrangements providing the Participant
                with substantially equivalent benefits) other than as a result
                of the normal expiration of any such Benefit Plan in accordance
                with its terms as in effect immediately prior to the Change of
                Control;

                        (vii)     any action or inaction by the Company that
                would adversely affect the Participant's continued
                participation in any Benefit Plan on at least as favorable a
                basis as was the case immediately prior to the Change of
                Control, or that would materially reduce the Participant's
                benefits in the future under the Benefit Plan or deprive him of
                any material benefits that he enjoyed immediately prior to the
                Change of Control, except to the extent that such action or
                inaction by the Company is required by the terms of the Benefit
                Plan as in effect immediately prior to the Change of Control,
                or is necessary to comply with applicable law or to preserve
                the qualification of the Benefit Plan under section 401(a) of
                the Code, and except to the extent that the Company provides
                the Participant with substantially equivalent benefits;

                        (viii)     the Company's failure to provide and credit
                the Participant with the number of days of paid vacation,
                holiday or leave to which he is then entitled in accordance
                with the Company's normal vacation, holiday or leave policy in
                effect immediately prior to the Change of Control;

                        (ix)     the imposition of any requirement that the
                Participant be based anywhere other than within 25 miles of
                where his principal office was located immediately prior to the
                Change of Control;

                        (x)     a material increase in the frequency or
                duration of the Participant's business travel; or

                        (xi)     any violation by the Company of any provision
                of this Plan.





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        Notwithstanding the foregoing, no action by the Company shall
        give rise to a Good Reason if it results from the Participant's
        termination for cause (as defined in the proviso in the definition of
        'Retirement,' above), Retirement, or death, and no action by the
        Company specified in subparts (i) through (iv) above shall give rise to
        a Good Reason if it results from the Participant's Disability. A Good
        Reason shall not be deemed to be waived by reason of the Participant's
        continued employment as long as the termination of the Participant's
        employment occurs within six months after the Good Reason arises or
        three years after the Change of Control, whichever occurs earlier. For
        purposes of this definition of termination for Good Reason, 'Benefit
        Plan' means any compensation plan, such as an incentive, stock option,
        or restricted stock plan, or any employee benefit plan, such as a
        thrift, pension, profit-sharing, stock bonus, long-term performance
        award, medical, disability, accident, or life insurance plan, or a
        relocation plan or policy, or any other plan, program or policy of the
        Company that is intended to benefit employees."

        4.     The Plan is hereby amended to add the following paragraph (d) to
Section 9.1:

                "(d) In the event of a Change of Control arising from a merger
        or sale of the stock or all or substantially all of the assets of
        Services and at such time (i) if the Participant's duties and
        responsibilities are principally in relation to the business of
        Services and (ii) such Participant is offered employment by Services or
        its successor or an affiliate thereof on terms at least as favorable as
        such Participant enjoyed immediately prior to such Change of Control
        (both (i) and (ii) as conclusively determined in its absolute
        discretion by the Administrative Committee), then whether or not such
        Participant accepts such offer of employment, such Participant shall
        not be entitled to any benefits under the Plan on account of such
        Change of Control and such Participant's participation in the Plan
        shall terminate effective with such Change of Control.




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        IN WITNESS WHEREOF, the Company has caused this Instrument to be
executed by its duly authorized officers and its corporate seal to be affixed
hereto as of the date first above written.



                                          CRS SIRRINE, INC.

                                                   /s/ Richard Daerr
                                          By ______________________________   
                                          Its   Executive Vice President

Attest:

      /s/ Frank Perrone
_______________________________
(Corporate Seal)





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