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EXHIBIT 10.73

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                    CORPORATE EXECUTIVE EMPLOYMENT AGREEMENT

THIS CORPORATE EXECUTIVE EMPLOYMENT AGREEMENT ("Agreement") is made as of
November 1, 2001, by and between HENRIK C. SLIPSAGER ("Executive"), and ABM
INDUSTRIES INCORPORATED ("Company") for itself and on behalf of its subsidiary
corporations as applicable herein.

WHEREAS, Company is engaged in the building maintenance and related service
businesses, and

WHEREAS, Executive is experienced in the administration, finance, marketing,
and/or operation of such services, and

WHEREAS, Company has invested significant time and money to develop proprietary
trade secrets and other confidential business information, as well as invaluable
goodwill among its customers, sales prospects and employees, and

WHEREAS, Executive wishes to, or has been and desires to remain employed by
Company, and to utilize such proprietary trade secrets, other confidential
business information and goodwill, and

WHEREAS, Company has disclosed or will disclose to Executive such proprietary
trade secrets and other confidential business information which Executive will
utilize in the performance of this Agreement;

NOW THEREFORE, Executive and Company agree as follows:

A.       EMPLOYMENT: Company hereby agrees to employ Executive, and Executive
         hereby accepts such employment, on the terms and conditions set forth
         in this Agreement.

B.       TITLE: Executive's title shall be President and Chief Executive Officer
         of Company, subject to modification as mutually agreed upon by both
         Company and Executive.

C.       DUTIES & RESPONSIBILITIES: Executive shall be expected to assume and
         perform such executive or managerial duties and responsibilities as are
         assigned from time-to-time by the Board of Directors of the Company, to
         whom Executive shall report and be accountable.

D.       TERM OF AGREEMENT: Employment hereunder shall be deemed effective as of
         November 1, 2001, for a term of two years ("Initial Term"), unless
         sooner terminated pursuant to Paragraph O hereof, or later extended
         pursuant to Paragraph N hereof ("Extended Term").

E.       PRINCIPAL OFFICE: During the Initial Term and any Extended Term, as
         applicable, of this Agreement, Executive shall be based at a Company
         office located in San Francisco in the state of California ("State of
         Employment"), or such other location as shall be mutually agreed upon
         by Company and Executive.

F.       COMPENSATION: Company agrees to compensate Executive, and Executive
         agrees to accept as compensation in full, for Executive's assumption
         and performance of duties and responsibilities pursuant to this
         Agreement:

         1.       SALARY: A salary paid in equal installments of no less
                  frequently than semi-monthly at the annual rate set forth in
                  Paragraph X.1 hereof ("Base Salary").

         2.       BONUS: A bonus or other incentive or contingent compensation,
                  if any, pursuant to Paragraph X.2. hereof.

         3.       FRINGE BENEFITS: Executive shall receive the then current
                  fringe benefits generally provided by Company to all of its
                  Executives. Such benefits may include but not be limited to
                  the use of a Company-leased car or a car allowance, group
                  health benefits, long-term disability benefits, group

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                  life insurance, sick leave and vacation. Each of these fringe
                  benefits is subject to the applicable Company policy at all
                  times. Executive expressly agrees that should he or she
                  terminate employment with Company for the purpose of being
                  re-employed by a Company affiliate, he or she shall
                  "carry-over" any accrued but unused vacation balance to the
                  books of the affiliate.

                  Company reserves the right to add, increase, reduce or
                  eliminate any fringe benefit at any time, but no such benefit
                  or benefits shall be reduced or eliminated as to Executive
                  unless generally reduced or eliminated as to comparable
                  executives within the Company.

         4.       LIMIT: To the extent that any compensation to be paid to
                  Executive under this Agreement would be non-deductible by the
                  Company as a result of the $1 million compensation limit
                  provisions of Section 162(m) of the Internal Revenue Code of
                  1986, as amended, (the "Code"), then such compensation shall
                  not be paid out to Executive at that time but shall instead be
                  deferred and paid without interest to Executive (subject to
                  applicable withholding and only to the extent that payment of
                  such deferred amount is fully deductible under Code Section
                  162(m)) in the first month of the taxable year following the
                  taxable year of the deferral. If the subsequent payment of the
                  deferral is itself subject to further deferral pursuant to
                  this Paragraph F.4, then such further deferred amount shall
                  instead be paid in the first month of the next following
                  taxable year.

G.       PAYMENT OR REIMBURSEMENT OF BUSINESS EXPENSES: Company shall pay
         directly or reimburse Executive for reasonable business expenses of
         Company incurred by Executive in connection with Company business, and
         approved in writing by the person(s) with the title set forth in
         Paragraph C hereof, upon presentation to such person(s) by Executive
         within sixty (60) days after incurring such expense of an itemized
         request for payment including the date, nature, recipient, purpose and
         amount of each such expense, accompanied by receipts for all such
         expenses in excess of Twenty-Five Dollars ($25) each.

H.       BUSINESS CONDUCT: Executive shall comply with all applicable laws
         pertaining to the performance of this Agreement, and with all lawful
         and ethical rules, regulations, policies, codes of conduct, procedures
         and instructions of Company, including but not limited to the
         following:

         1.       GOOD FAITH: Executive shall not act in any way contrary to the
                  best interest of Company.

         2.       BEST EFFORTS: During all full-time employment hereunder,
                  Executive shall devote full working time and attention to
                  Company, and shall not at any time be directly or indirectly
                  employed by, own, operate, assist or otherwise be involved,
                  invested or associated in any business that is similar or
                  competitive to any business of Company; except that Executive
                  may own up to five percent (5%) of any such publicly-held
                  business(es), provided that Executive: (a) shall give Company
                  notice(s) of such ownership in accordance with Paragraph W
                  hereof, and (b) shall not at any time be directly or
                  indirectly employed by or operate, assist, or otherwise be
                  involved or associated with any such business(es).

         3.       VERACITY: Executive shall make no claims or promises to any
                  employee, supplier, contractor, customer or sales prospect of
                  Company that are unauthorized by Company or are in any way
                  untrue.

         4.       DRIVER'S LICENSE: Executive shall have and carry a valid
                  driver's license issued by his or her state of domicile or the
                  State of Employment hereunder and a driver's permit issued by
                  the Company whenever Executive is driving any motor vehicle in
                  connection with Company business. Executive agrees to
                  immediately notify Company in writing if Executive's driver's
                  license is lost, expired, restricted, suspended or revoked for
                  any reason whatsoever.

I.       NO CONFLICT: Executive represents to Company that Executive is not
         bound by any contract with a previous employer or with any other
         business that might prevent Executive from entering into this
         Agreement. Executive further represents that he or she is not bound by
         any other contracts or covenants

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         that in any way restrict or limit Executive's activities in relation to
         his or her employment with Company that have not been fully disclosed
         to Company prior to the signing of this Agreement.

J.       COMPANY PROPERTY: Company shall, from time to time, entrust to the
         care, custody and control of Executive certain of Company's property,
         such as motor vehicles, equipment, supplies and documents. Such
         documents may include, but shall not be limited to customer lists,
         financial statements, cost data, price lists, invoices, forms,
         electronic files and media, mailing lists, contracts, reports, manuals,
         personnel files or directories, correspondence, business cards, copies
         or notes made from Company documents and documents compiled or prepared
         by Executive for Executive's use in connection with Company business.
         Executive specifically acknowledges that all such documents are the
         property of Company, notwithstanding their preparation, care, custody,
         control or possession by Executive at any time(s) whatsoever.

K.       GOODWILL & PROPRIETARY INFORMATION: In connection with Executive's
         employment hereunder:

         1.       Executive agrees to utilize and further Company's goodwill
                  ("Goodwill") among its customers, sales prospects and
                  employees, and acknowledges that Company may disclose to
                  Executive and Executive may disclose to Company, proprietary
                  trade secrets and other confidential information not in the
                  public domain ("Proprietary Information") including but not
                  limited to specific customer data such as: (a) the identity of
                  Company's customers and sales prospects, (b) the nature,
                  extent, frequency, methodology, cost, price and profit
                  associated with its services and products purchased from
                  Company, (c) any particular needs or preferences regarding its
                  service or supply requirements, (d) the names, office hours,
                  telephone numbers and street addresses of its purchasing
                  agents or other buyers, (e) its billing procedures, (f) its
                  credit limits and payment practices, and (g) its organization
                  structure.

         2.       Executive agrees that such Proprietary Information and
                  Goodwill have unique value to Company, are not generally known
                  or readily available to Company's competitors, and could only
                  be developed by others after investing significant time and
                  money. Company would not make such Proprietary Information and
                  Goodwill available to Executive unless Company is assured that
                  all such Proprietary Information and Goodwill will be held in
                  trust and confidence by Executive. Executive hereby
                  acknowledges that to use this Proprietary Information and
                  Goodwill except for the benefit of Company would be a breach
                  of such trust and confidence and in violation of Executive's
                  common law Duty of Loyalty to the Company.

L.       RESTRICTIVE COVENANTS: In recognition of Paragraph K, above, Executive
         hereby agrees that during the Initial Term and the Extended Term, if
         any, of this Agreement, and thereafter as specifically agreed herein:

         1.       Except in the proper performance of this Agreement, Executive
                  shall at no time directly or indirectly solicit or otherwise
                  encourage or arrange for any employee to terminate employment
                  with Company.

         2.       Except in the proper performance of this Agreement, Executive
                  shall not directly or indirectly disclose or deliver to any
                  other person or business, any Proprietary Information obtained
                  directly or indirectly by Executive from, or for, Company.

         3.       Executive agrees that at all times after the termination of
                  this Agreement, Executive shall not seek, solicit, divert,
                  take away, obtain or accept the patronage of any customer or
                  sales prospect of Company through the direct or indirect use
                  of any Proprietary Information of Company, or by any other
                  unfair or unlawful business practice.

         4.       Executive agrees that for a reasonable time after the
                  termination of this Agreement, which Executive and Company
                  hereby agree to be one (1) year, Executive shall not directly
                  or indirectly, for Executive or for any other person or
                  business, seek, solicit, divert, take away, obtain or accept

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                  any customer account or sales prospect with which Executive
                  had direct business involvement on behalf of Company within
                  the one (1) year period prior to termination of this
                  Agreement.

         5.       Nothing in this Agreement shall be binding upon the parties to
                  the extent it is void or unenforceable for any reason in the
                  State of Employment, including, without limitation, as a
                  result of any law regulating competition or proscribing
                  unlawful business practices.

M.       MODIFICATION OF EMPLOYMENT: At any time during the then current Initial
         or Extended Term, as applicable, of this Agreement, a majority of the
         Board of Directors of Company shall have the absolute right, with or
         without cause and without terminating this Agreement or Executive's
         employment hereunder, to modify the nature of Executive's employment
         for the remainder of the then current Initial or Extended Term, as
         applicable, of this Agreement, from that of a full-time employee to
         that of a part-time employee ("Modification Period"). The Modification
         Period shall commence immediately upon Company giving Executive written
         notice of such change.

         1.       Upon commencement of the Modification Period: (a) Executive
                  shall immediately resign as a full-time employee of Company
                  and as an officer and/or director of Company, as applicable,
                  (b) Executive shall promptly return all Company property in
                  Executive's possession to Company, including but not limited
                  to any motor vehicles, equipment, supplies and documents set
                  forth in Paragraph J hereof, and (c) Company shall pay
                  Executive all previously earned and vested but as yet unpaid,
                  salary, prorated bonus or other contingent compensation,
                  reimbursement of business expenses and fringe benefits.

         2.       During the Modification Period: (a) Company shall continue to
                  pay Executive's monthly salary pursuant to Paragraph F.1
                  hereof, and to the extent available under the Company's group
                  insurance policies, continue to provide Executive with the
                  same group health and life insurance (subject to Executive
                  continuing to pay the employee portion of any such premium) to
                  which Executive would be entitled as a full-time employee,
                  with the understanding and agreement that such monthly salary
                  and group insurance, if available, shall constitute the full
                  extent of Company's obligation to compensate Executive, (b)
                  Executive shall not be eligible or entitled to receive or
                  participate in any bonus or fringe benefits other than the
                  aforementioned group insurance, if available, (c) in the
                  alternative, Executive may exercise rights under COBRA to
                  obtain medical insurance coverage as may be available to
                  Executive, (d) Executive shall be deemed a part-time employee
                  and not a full-time employee of Company, (e) Executive shall
                  provide Company with such occasional executive or managerial
                  services as reasonably requested by the person(s) with the
                  title set forth in Paragraph C hereof, except that failure to
                  render such services by reason of any physical or mental
                  illness or disability other than Total Disability or death as
                  set forth in Paragraph O.2 hereof, or unavailability because
                  of absence from the State of Employment hereunder, shall not
                  affect Executive's right to receive such salary and (f)
                  Company shall pay directly or reimburse Executive in
                  accordance with the provisions of Paragraph G hereof for
                  reasonable business expenses of Company incurred by Executive
                  in connection with such services requested by the person(s)
                  with the title set forth in Paragraph C hereof.

         3.       The Modification Period shall continue until the earlier of:
                  (a) Total Disability or death as set forth in Paragraph O.2
                  hereof, (b) termination of this Agreement by Company for "just
                  cause" as hereinafter defined, (c) Executive accepting
                  employment or receiving any other compensation from operating,
                  assisting or otherwise being involved, invested or associated
                  with any business that is similar to or competitive with any
                  business in which Company is engaged on the commencement date
                  of the Modification Period, or (d) expiration of the then
                  current Term of this Agreement.

N.       EXTENSION OF EMPLOYMENT:

         1.       Absent at least ninety (90) days written Notice of Termination
                  of Employment or Notice of Non-Renewal from Company to
                  Executive prior to expiration of the then current Initial or
                  Extended Term, as applicable, of this Agreement, employment
                  hereunder shall continue for an Extended

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                  Term (or another Extended Term, as applicable) of one year, by
                  which Executive and Company intend that all terms and
                  conditions of this Agreement shall remain in full force and
                  effect for another twelve (12) months, except that the highest
                  base salary specified in Paragraph X.1.a shall be increased
                  annually as set forth in Paragraph X.1.b for each year of the
                  Extended Term.

         2.       In the event that Notice of Non-Renewal is given ninety (90)
                  days prior to the expiration of the then Initial or Extended
                  Term, as applicable, of this Agreement, employment shall
                  continue on an "at will" basis. In such event, Company shall
                  have the right to change the terms and conditions of
                  Executive's employment, including but not limited to
                  Executive's position and/or compensation.

O.       TERMINATION OF EMPLOYMENT:

         1.       a.       Subject to at least ninety (90) days prior written
                           Notice of Termination of Employment, Executive's
                           employment shall terminate, with or without cause, at
                           the expiration of the then current Initial or
                           Extended Term. Company has the option, without
                           terminating this Agreement, of placing Executive on a
                           leave of absence at the full compensation set forth
                           in Paragraph F hereof, for any or all of such notice
                           period.

                  b.       Except as provided in Paragraph O.1.a, the Company
                           shall have the right to terminate Executive's
                           employment hereunder at any time during the then
                           current Initial or Extended Term, as applicable, of
                           this Agreement, without notice subject only to a good
                           faith determination by a majority of the Board of
                           Directors of Company of "just cause." "Just cause"
                           includes but is not limited to any (i) theft or other
                           dishonesty, (ii) neglect of or failure to perform
                           employment duties, (iii) inability or unwillingness
                           to perform employment duties, (iv) insubordination,
                           (v) abuse of alcohol or other drugs or substances,
                           (vi) breach of this Agreement; (vii) other
                           misconduct, unethical or unlawful activity, or for
                           (viii) a conviction of or plea of "guilty" or "no
                           contest" to a felony under the laws of the United
                           States or any state thereof.

                  c.       At any time during the then current Initial or
                           Extended Term, as applicable, of this Agreement, with
                           or without cause, Executive may terminate employment
                           hereunder by giving Company ninety (90) days prior
                           written notice.

         2.       Employment hereunder shall automatically terminate upon the
                  total disability ("Total Disability") or death of Executive.
                  Total Disability shall be deemed to occur on the ninetieth
                  (90th) consecutive or non-consecutive calendar day within any
                  twelve (12) month period that Executive is unable to perform
                  the duties set forth in Paragraph C hereof because of any
                  physical or mental illness or disability. Company shall pay
                  when due to Executive or, upon death, Executive's designated
                  beneficiary or estate, as applicable, all prorated salary,
                  bonus or other contingent compensation, reimbursement of
                  business expenses and fringe benefits which would have
                  otherwise been payable to Executive under this Agreement,
                  through the end of the month in which Total Disability or
                  death occurs.

         3.       Upon termination of employment hereunder, Executive shall
                  immediately resign as an employee of Company and as an officer
                  and/or director of Company, as applicable. Executive shall
                  promptly return all Company property in Executive's possession
                  to Company, including but not limited to, any motor vehicles,
                  equipment, supplies and documents set forth in Paragraph J
                  hereof. Company shall pay Executive, when due, all previously
                  earned and vested but as yet unpaid, salary, bonus or other
                  contingent compensation, reimbursement of business expenses
                  and fringe benefits.

P.       GOVERNING LAW: This Agreement shall be interpreted and enforced in
         accordance with the laws of the State of Employment hereunder.

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Q.       ARBITRATION CLAUSE:

         1.       Except for the interpretation and enforcement of injunctive
                  relief pursuant to Paragraph R hereof (which shall be subject
                  to litigation in any court having proper jurisdiction), any
                  claim or dispute related to or arising from this Agreement
                  (whether based in contract or tort, in law or equity)
                  including, but not limited to, claims or disputes between
                  Executive and Company or its directors, officers, employees
                  and agents regarding Executive's employment or termination of
                  employment hereunder, or any other business of Company, shall
                  be resolved by a neutral arbitrator agreed upon by both
                  parties, through mandatory, final, binding arbitration in
                  accordance with the procedural and discovery rules of the
                  American Arbitration Association.

         2.       The cost of such arbitration shall be borne by the Company.
                  Any such arbitration must be requested in writing within one
                  (1) year from the date the party initiating the arbitration
                  knew or should have known about the claim or dispute, or all
                  claims arising from that dispute are forever waived. Any such
                  arbitration (or court proceeding as applicable hereunder)
                  shall be held in the city and/or county of employment
                  hereunder. Judgment upon the award rendered through such
                  arbitration may be entered and enforced in any court having
                  proper jurisdiction.

R.       REMEDIES & DAMAGES:

         1.       The parties agree that, in the event of a material breach or
                  threatened material breach of Paragraphs K and/or L hereof,
                  the damage or imminent damage to the value of Company's
                  business shall be impractical and/or impossible to estimate or
                  ascertain, and therefore any remedy at law or in damages shall
                  be inadequate. Accordingly, the parties hereto agree that
                  Company shall be entitled to the immediate issuance of a
                  restraining order or an injunction against Executive in the
                  event of such breach or threatened breach, in addition to any
                  other relief available to Company pursuant to this Agreement
                  or under law.

         2.       Executive agrees that the actual amount of damages resulting
                  from any material breach of any of the provisions of
                  Paragraphs K and/or L hereof would be impractical or
                  impossible to estimate or ascertain. It is therefore agreed
                  that the damages resulting from any such breach which involves
                  any customer of Company shall be liquidated damages, not a
                  penalty, in an amount equal to four (4) times the lost monthly
                  revenue to the Company based on the average monthly revenue
                  which was payable by that customer to Company during the four
                  (4) months immediately preceding such breach. This provision
                  for liquidated damages is in addition to any other relief
                  available to Company pursuant to this Agreement or under law.

         3.      To the full extent permitted under the laws of the State of
                 Employment hereunder, Executive authorizes Company to withhold
                 from Executive's compensation and from any other funds held for
                 Executive's benefit by Company, any damages or losses sustained
                 by Company as a result of any material breach or other material
                 violation of this Agreement by Executive, pending arbitration
                 between the parties as provided for herein.

S.       NO WAIVER: Failure by either party to enforce any term or condition of
         this Agreement at any time shall not preclude that party from enforcing
         that provision, or any other provision of this Agreement, at any later
         time.

T.       SEVERABILITY: The provisions of this Agreement are severable. If any
         arbitrator (or court as applicable hereunder) rules that any portion of
         this Agreement is invalid or unenforceable, the arbitrator's or court's
         ruling shall not affect the validity and enforceability of other
         provisions of this Agreement. It is the intent of the parties that if
         any provision of this Agreement is ruled to be overly broad, the
         arbitrator or court shall interpret such provision with as much
         permissible breadth as is allowable under law rather than to consider
         such provision void.

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U.       SURVIVAL: All terms and conditions of this Agreement which by
         reasonable implication are meant to survive the termination of this
         Agreement, including but not limited to the Restrictive Covenants and
         Arbitration Clause herein, shall remain in full force and effect after
         the termination of this Agreement.

V.       CONSTRUCTION: This Agreement was negotiated in good faith by the
         parties hereto, who hereby agree to share the responsibility for any
         ambiguities, uncertainties or inconsistencies herein. Paragraph
         headings are used herein only for ease of reference, and shall not in
         any way affect the interpretation or enforcement of this Agreement.

W.       NOTICES:

         1.       Any notice required or permitted to be given pursuant to this
                  Agreement shall be in writing and delivered in person, or sent
                  prepaid by certified mail, bonded messenger or overnight
                  express, to the party named at the address set forth below or
                  at such other address as either party may hereafter designate
                  in writing to the other party:

                  EXECUTIVE:        HENRIK C. SLIPSAGER
                                    17 Stratton Road
                                    Purchase, NY10577

                  COMPANY:          ABM INDUSTRIES INCORPORATED
                                    160 Pacific Avenue, Suite 222
                                    San Francisco, CA  94111
                                    Attention:  Chairman of the Board

                  COPY:             ABM INDUSTRIES INCORPORATED
                                    160 Pacific Avenue, Suite 222
                                    San Francisco, CA  94111
                                    Attention: Chief Employment Counsel

         2.       Any such Notice shall be assumed to have been received when
                  delivered in person, or forty-eight (48) hours after being
                  sent in the manner specified above.

X.       SPECIAL PROVISIONS:

         1.       SALARY:

                  a.       Six Hundred Fifty Thousand Dollars ($650,000) per
                           year effective November 1, 2001 through October 31,
                           2002 at the monthly rate of $54,166.67 payable
                           semi-monthly.

                  b.       Effective November 1, 2002 through October 31, 2003
                           the Salary in Paragraph X.1.a. will be adjusted
                           upward to reflect the percentage increase change in
                           the WorldatWork (TM)/(formerly, the American
                           Compensation Association) Total Salary Increase
                           Budget Survey for the Western Region ("ACA Index")
                           with a six percent (6%) maximum increase. The
                           adjustment, if any, shall be based upon the projected
                           ACA Index as published for the current year,
                           immediately preceding the effective date of the
                           proposed increase hereunder. Notwithstanding the
                           foregoing, there shall be no annual increase in
                           Salary for such year unless the Company's net
                           earnings per share ("EPS"), excluding WTC Related
                           Gain (as defined below) for the fiscal year of the
                           Company, commencing November 1 and ending October 31
                           ("Fiscal Year"), then ending are equal to or greater
                           than the Company's EPS for the previous Fiscal Year.

         2.       BONUS: Subject to proration in the event of modification or
                  termination of employment hereunder and further subject to the
                  potential prospective re-set provisions set forth in
                  Subparagraph c, below ("Reset"), Executive shall be paid a
                  bonus ("Bonus") based on the profit ("Profit") for each Fiscal

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                  Year, or partial Fiscal Year, of employment hereunder during
                  the Initial Term, and during the Extended Term, if any, of
                  this Agreement, as follows:

                  a.       Subject to the maximum bonus payable under
                           subparagraph c., such Bonus for each Fiscal Year
                           shall be 0.2519% of the Company's Profit on a
                           pro-rata basis.

                  b.       Profit for purposes of determining such Bonus, shall
                           be defined as the consolidated income (in accordance
                           with generally accepted accounting principles) before
                           income taxes of the Company, excluding: (i) gains or
                           losses on sales or exchanges of real property or on
                           sales or exchanges of all or substantially all of the
                           stock or assets of a subsidiary corporation or any
                           other business unit of Company, (ii) gains or losses
                           on the discontinuation of any business unit of
                           Company, (iii) the discretionary portion of any
                           contributions made to any profit sharing, employee
                           retirement savings or similar plan and (iv) WTC
                           Related Gain. At any time the Board of Directors of
                           the Company (the "Board") reserves the right to
                           further adjust Profit for purposes of determining a
                           Bonus in the event of a Significant Transaction (as
                           defined below) during a Fiscal Year and/or for any
                           unanticipated and material events that are beyond the
                           control of the Company, including but not limited to
                           acts of god, nature, war or terrorism, or changes in
                           the rules for financial reporting set forth by the
                           Financial Accounting Standards Board, the Securities
                           and Exchange Commission, and/or the New York Stock
                           Exchange or for any other reason which the Board
                           determines, in good faith, to be appropriate.

                           Notwithstanding the foregoing, Profit for purposes of
                           determining the Bonus in any Fiscal Year during the
                           Initial or Extended Term of this Agreement, shall
                           include WTC Related Gain and WTC Related Carry-Over
                           Gain in an aggregate amount not to exceed a maximum
                           of $10 million per Fiscal Year. For purposes of this
                           Agreement, the term "WTC Related Gain" shall mean the
                           total amount of all items of income included in the
                           Company's audited consolidated financial statements
                           for any Fiscal Year that result from the Company's
                           receipt of insurance proceeds or other compensation
                           or damages due to the Company's loss of property,
                           business or profits as a result of the destruction of
                           the World Trade Center on September 11, 2001. Also,
                           for purposes of this Agreement, the term "WTC Related
                           Carry-Over Gain" shall mean the aggregate amount of
                           WTC Related Gain not previously taken into account in
                           determining a Bonus for a prior Fiscal Year. Finally,
                           for purposes of this Agreement, the term "Significant
                           Transaction" shall mean the Company's acquisition or
                           disposition of a business or assets which the Company
                           is required to report under Item 2 of the SEC Form
                           8-K.

                  c.       Subject to proration in the event of modification or
                           termination of employment under this Agreement, and
                           further subject to a Reset in the event Executive's
                           Bonus for Fiscal Year 2002 has been limited as
                           hereinafter provided, Executive's maximum Bonus for
                           each Fiscal Year shall be one hundred percent (100%)
                           of the Base Salary for that year set forth in this
                           Agreement. If, however, in Fiscal Year 2002 the Bonus
                           which might have been earned by Executive for that
                           year exceeds said one hundred percent (100%) maximum,
                           Executive's Base Salary and Bonus percentage for
                           Fiscal Year 2003 shall be Reset as follows: (i)
                           notwithstanding the six percent (6%) maximum set
                           forth in paragraph X.1.b. of the Agreement, the
                           Executive's Salary shall be adjusted to equal
                           seventy-five percent (75%) of the prior Fiscal Year's
                           combined Salary and Bonus, plus an amount equal to
                           the increase, if any, set forth in Paragraph X.1.b of
                           the Agreement based upon said ACA Index; and (ii) the
                           Bonus percentage set forth in Subparagraph a (above)
                           shall be adjusted by multiplying the prior Fiscal
                           Year's combined Salary and Bonus by twenty-five
                           percent (25%), and dividing that product by the
                           actual Profit earned in the prior Fiscal Year.

                  d.       The Chief Financial Officer of the Company shall
                           calculate the Profit and Bonus for purposes of this
                           Agreement. Company shall pay Executive the Bonus for
                           the Fiscal Year following completion of the audit of
                           the Company's financial statements, but no later than

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                                                                    Page 9 of 10

                           seventy-five (75) days after the end of each Fiscal
                           Year. The Company in its sole discretion may pay any
                           Bonus earlier. The Bonus for any partial Fiscal Year
                           shall be prorated for the fraction of the Fiscal Year
                           for which such Bonus is payable. Absent bad faith or
                           material error, any calculations of the Chief
                           Financial Officer and any conclusions of the Board,
                           with respect to the amounts of the Profit or Bonus,
                           shall be final and binding upon Executive and
                           Company.

                  e.       Notwithstanding the foregoing, no Bonus for any
                           Fiscal Year of the Company shall be payable unless
                           the Company's EPS for the Fiscal Year then ending is
                           equal to or greater than eighty percent (80%) of the
                           Company's EPS for the previous Fiscal Year of the
                           Company, in each case excluding any WTC Related Gain.

                  f.       Nothing contained in this Agreement shall entitle
                           Executive to receive a bonus or other incentive or
                           contingent compensation from Company based on any
                           sales or profits made (including but not limited to
                           any WTC Related Gain or WTC Related Carry-Over Gain
                           realized) by Company after termination of the Initial
                           or Extended Term of this Agreement or of employment
                           hereunder.

                  g.       Notwithstanding any other provision hereof, the Board
                           may, prior to the beginning of any Fiscal Year,
                           approve and notify the Executive of a modification to
                           the Bonus percentage determined hereunder (either
                           higher or lower), based on such performance and
                           financial measures and other factors as the Board
                           shall determine in its sole discretion. The Board's
                           decision in this regard shall be deemed final and
                           binding on Executive regardless of the amount of
                           Bonus otherwise calculated pursuant to the foregoing
                           provisions. In addition, the Board reserves the
                           option at any time to grant a discretionary incentive
                           bonus, which shall not be subject to the maximum
                           Bonus or Reset provisions described in paragraph
                           X.2.c. above.

                  h.       Executive herein acknowledges receipt of Bonus for
                           Fiscal Year 2001 and agrees that he or she is not
                           entitled to any further bonus for that year, for any
                           reason whatsoever.

         3.       SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN ("SERP") Following
                  Executive's retirement, resignation and/or termination from
                  employment with Company (but commencing no earlier than what
                  is or would have been Executive's sixty-fifth (65th) birthday
                  and concluding no later than ten (10) years thereafter),
                  Company shall pay to Executive: 120 equal monthly installments
                  each of 1/120th of the Supplemental Benefit accrued, pursuant
                  to the terms of the Plan Document, provided herewith.

         4.       POST-EMPLOYMENT CONSULTANCY: After Executive's retirement,
                  resignation and/or termination from employment with Company,
                  but commencing no earlier than what is or would have been
                  Executive's sixty-fifth (65th) birthday and concluding no
                  later than ten (10) years thereafter ("Consultancy Period"),
                  the Company shall provide Executive and his spouse with
                  reimbursement for dental coverage comparable to that provided
                  to other Company executive officers together with the coverage
                  commonly known as Medicare Supplement or Medigap Insurance to
                  supplement Medicare coverage furnished by the federal
                  government to retirees; provided however that Executive and
                  his spouse shall pay Company the then current premium
                  contribution charged by Company to its executive officers for
                  their medical and dental coverage, and Company's cost of such
                  reimbursement shall not exceed a combined amount of $10,000 in
                  any Fiscal Year for Executive and his spouse, or $5,000 in the
                  event of the death of either.

                  In consideration for the above, during the Consultancy Period:
                  (a) Executive shall provide Company with such occasional
                  executive or managerial services as reasonably requested by
                  the Company, (b) Company shall pay directly or reimburse
                  Executive for reasonable business expenses of Company incurred
                  by Executive in connection with such services upon
                  presentation to that person by Executive within sixty (60)
                  days after incurring such expense of an itemized

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                                                                   Page 10 of 10

                  request for payment including the date and receipts for all
                  such expenses in excess of Twenty-Five Dollars ($25) each, (c)
                  Executive shall not be eligible or entitled to receive or
                  participate in any other of the Company's then current fringe
                  benefits and (d) Executive shall be deemed an independent
                  contractor and not an employee of Company.

Y.       SCOPE OF CERTAIN PROVISIONS: All references to Company in Paragraphs H,
         J, K, L, O.3 and R in this Agreement shall include Company, and its
         subsidiary corporations and other Company affiliates.

Z.       ENTIRE AGREEMENT: Unless otherwise specified herein, this Agreement
         sets forth every contract, understanding and arrangement as to the
         employment relationship between Executive and Company, and may only be
         changed by a written amendment signed by both Executive and Company.

         1.       The parties intend that this Agreement speak for itself, and
                  that no evidence with respect to its terms and conditions
                  other than this Agreement itself may be introduced in any
                  arbitration or judicial proceeding to interpret or enforce
                  this Agreement.

         2.       It is specifically understood and accepted that this Agreement
                  supersedes all oral and written employment agreements between
                  Executive and Company prior to the date hereof, as well as all
                  conflicting provisions of Company's Guidelines for Corporate
                  Approval and its Human Resources Manual, including but not
                  limited to the termination, discipline and discharge
                  provisions contained therein.

         3.       This Agreement may not be amended except in a writing signed
                  by the Executive and two (2) officers of the Company, and
                  approved by the Company's Board of Directors.

FULL KNOWLEDGE & UNDERSTANDING: Executive and Company hereby acknowledge that
they have carefully read and fully understand all terms and conditions of this
Agreement, that they have been given an opportunity to review all aspects of
this Agreement with an attorney if they so choose, and that they are voluntarily
entering into this Agreement with full knowledge of the benefits and burdens,
and the risks and rewards, contained herein.

IN WITNESS WHEREOF, Executive and two (2) Directors of the Company have executed
this Agreement as of the date set forth above:

     EXECUTIVE:  Signature:  /s/ Henrik C. Slipsager
                            ----------------------------------------------------

                 Date:       9/30/02
                            ----------------------------------------------------

     COMPANY:               ABM INDUSTRIES INCORPORATED

                 Date:       10/10/02
                            ----------------------------------------------------

                 Signature:  /s/ Maryellen C. Herringer
                            ----------------------------------------------------

                 Title:      Chair, Compensation Committee, Board of Directors
                            ----------------------------------------------------

                 Signature:  /s/ Henry L. Kotkins
                            ----------------------------------------------------

                 Title:      Member, Compensation Committee, Board of Directors
                            ----------------------------------------------------

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