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                                                                   EXHIBIT 10.10

                      CHANGE IN CONTROL SEVERANCE AGREEMENT

Mr. Douglas A Carty

85 Drake Smith Lane

Rye, New York, 10580

Dear Douglas:

         Laidlaw Inc. (the "Company") recognizes that, as is the case for most
companies, the possibility of a change in control exists. The Company wishes to
ensure that its senior executives are not distracted from performing their
duties in the event of a proposed or actual transaction involving a change in
control. Accordingly, the Company has determined that as an additional
inducement for you (the "Executive") to continue to remain in the employ of the
Company and to assure itself of both present and future continuity of
management, the Company agrees to provide the Executive with severance benefits
under the following circumstances pursuant to the following terms and conditions
(the "Agreement"):

1.                Certain Defined Terms. In addition to terms defined elsewhere
         herein, the following terms have the following meanings when used in
         this Agreement with initial capital letters:

         (a)               "Base Pay" means the Executive's annual base salary
                  rate as in effect from time to time.

         (b)               "Board" means the Board of Directors of the Company.

         (c)               "Cause" means that, prior to any termination pursuant
                  to Section 3(b), the Executive shall have:

                  (i)      engaged in misconduct which is materially injurious
                           to the Company, monetarily or otherwise;

                  (ii)     committed an act of fraud, embezzlement or theft in
                           connection with his duties or in the course of his
                           employment with the Company or any subsidiary;

                  (iii)    intentionally damaged property of the Company or any
                           subsidiary;

                  (iv)     committed wrongful disclosure of secret processes or
                           confidential information of the Company or any
                           Subsidiary; or

                  (v)      engaged in any Competitive Activity;

                           and any such act shall have been demonstrably and
                           materially harmful to

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                           the Company. Notwithstanding the foregoing, the
                           Executive shall not be deemed to have been terminated
                           for "Cause" hereunder unless and until there shall
                           have been delivered to the Executive a copy of a
                           resolution duly adopted by the affirmative vote of
                           not less than a majority of the Board then in office
                           (excluding the Executive if he is a Director) at a
                           meeting of the Board called and held for such
                           purpose, after reasonable notice to the Executive and
                           an opportunity for the Executive, together with the
                           Executive's counsel (if the Executive chooses to have
                           counsel present at such meeting), to be heard before
                           the Board, finding that, in the good faith opinion of
                           the Board, the Executive had committed an act
                           constituting "Cause" as herein defined and specifying
                           the particulars thereof in detail. Nothing herein
                           will limit the right of the Executive or his
                           beneficiaries to contest the validity or propriety of
                           any such determination;

         (d)               "Change in Control" means the occurrence during the
                  Term of any of the following events:

                  (i)      the acquisition by any individual, entity or group
                           (within the meaning of Section 13(d)(3) or 14(d)(2)
                           of the Exchange Act) (a "Person") of beneficial
                           ownership (within the meaning of Rule 13d-3
                           promulgated under the Exchange Act) of 50% or more of
                           the then-outstanding Voting Stock; provided, however,
                           that the following acquisitions shall not constitute
                           a Change in Control: (A) any acquisition directly
                           from the Company, (B) any acquisition by the Company,
                           (C) any acquisition by any employee benefit plan (or
                           related trust) sponsored or maintained by the Company
                           or any Subsidiary or (D) any acquisition by any
                           Person pursuant to a transaction that complies with
                           clauses (A), (B) and (C) of subsection (iii) of this
                           Section 1(d);

                  (ii)     individuals who, as of the date hereof, constitute
                           the Board (the "Incumbent Board") cease for any
                           reason (other than death or disability) to constitute
                           at least a majority of the Board; provided, however,
                           that any individual becoming a director subsequent to
                           the date hereof whose election, or nomination for
                           election by the Company's stockholders, was approved
                           by a vote of at least a majority of the directors
                           then comprising the Incumbent Board (either by a
                           specific vote or by approval of the proxy statement
                           of the Company in which such person is named as a
                           nominee for director, without objection to such
                           nomination) shall be considered as though such
                           individual were a member of the Incumbent Board, but
                           excluding for this purpose, any such individual whose
                           initial assumption of office occurs as a result of an
                           actual or threatened election contest (within the
                           meaning of Rule 14a-11 of the Exchange Act) with
                           respect to the election or removal of directors or
                           other actual or threatened solicitation of proxies or
                           consents by or on behalf of a Person other than the
                           Board;

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                  (iii)    consummation of a reorganization, merger or
                           consolidation or sale or other disposition of all or
                           substantially all of the assets of the Company (a
                           "Business Combination"), unless, in each case,
                           immediately following such Business Combination, (A)
                           all or substantially all of the individuals and
                           entities who were the beneficial owners of Voting
                           Stock of the Company immediately prior to such
                           Business Combination beneficially own, directly or
                           indirectly, more than 50% of the then outstanding
                           shares of common stock and the combined voting power
                           of the then outstanding voting securities entitled to
                           vote generally in the election of directors of the
                           entity resulting from such Business Combination
                           (including, without limitation, an entity which as a
                           result of such transaction owns the Company or all or
                           substantially all of the Company's assets either
                           directly or through one or more subsidiaries) in
                           substantially the same proportions relative to each
                           other as their ownership, immediately prior to such
                           Business Combination, of the Voting Stock of the
                           Company, (B) no Person (excluding any entity
                           resulting from such Business Combination or any
                           employee benefit plan (or related trust) sponsored or
                           maintained by the Company, any Subsidiary or such
                           entity resulting from such Business Combination)
                           beneficially owns, directly or indirectly, 15% or
                           more of the then outstanding shares of common stock
                           of the entity resulting from such Business
                           Combination or the combined voting power of the then
                           outstanding voting securities of such entity except
                           to the extent such ownership existed prior to the
                           Business Combination and (C) at least a majority of
                           the members of the board of directors of the entity
                           resulting from such Business Combination were members
                           of the Incumbent Board at the time of the execution
                           of the initial agreement or of the action of the
                           Board providing for such Business Combination; or

                  (iv)     approval by the stockholders of the Company of a
                           complete liquidation or dissolution of the Company.

         (e)               "Competitive Activity" means the Executive's
                  participation, without the written consent of the Board, as an
                  employee, officer, consultant or director of any business
                  enterprise if such enterprise engages in substantial and
                  direct competition with the Company and such enterprise's
                  sales of any product or service competitive with any product
                  or service of the Company amounted to 10% of such enterprise's
                  net sales for its most recently completed fiscal year and if
                  the Company's net sales of said product or service amounted to
                  10% of the Company's net sales for its most recently completed
                  fiscal year. "Competitive Activity" will not include (i) the
                  mere ownership of securities in any such enterprise and the
                  exercise of rights appurtenant thereto or (ii) participation
                  in the management of any such enterprise other than in
                  connection with the competitive operations of such enterprise.

         (f)               "Employee Benefits" means the perquisites, benefits
                  and service credit for benefits as provided under any and all
                  employee retirement income and welfare benefit policies,
                  plans, programs or arrangements in which Executive is entitled
                  to

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                  participate, including, without limitation, any stock option,
                  performance share, performance unit, stock purchase, stock
                  appreciation, savings, pension, supplemental executive
                  retirement, or other retirement income or welfare benefit,
                  deferred compensation, incentive compensation, group or other
                  life, health, medical/hospital or other insurance (whether
                  funded by actual insurance or self-insured by the Company or
                  a Subsidiary), disability, salary continuation, expense
                  reimbursement and other employee benefit policies, plans,
                  programs or arrangements.

         (g)               "Exchange Act" means the Securities Exchange Act of
                  1934.

         (h)               "Incentive Pay" means an annual bonus, incentive or
                  other payment of compensation, in addition to Base Pay, made
                  or to be made in regard to services rendered in any year or
                  other period pursuant to any bonus, incentive, profit-sharing,
                  performance, discretionary pay or similar agreement, policy,
                  plan, program or arrangement (whether or not funded) of the
                  Company or a Subsidiary, or any successor thereto.

         (i)               "Retirement Plans" means the retirement income,
                  supplemental executive retirement, excess benefits and retiree
                  medical, life and similar benefit plans, programs or
                  arrangements of the Company in which the Executive is entitled
                  to participate.

         (j)               "Severance Period" means the period of time
                  commencing on the date of the first occurrence of a Change in
                  Control and continuing until the earlier of (i) the second
                  anniversary of the occurrence of the Change in Control, or
                  (ii) the Executive's death.

         (k)               "Subsidiary" means an entity in which the Company
                  directly or indirectly beneficially owns 50% or more of the
                  outstanding Voting Stock.

         (l)               "Term" means the period commencing as of the date
                  hereof and expiring as of the later of (i) the close of
                  business on August 31, 2003, or (ii) the expiration of the
                  Severance Period; provided, however, that (A) commencing on
                  September 1, 2004 and each September 1 thereafter, the term of
                  this Agreement will automatically be extended for an
                  additional year unless, not later than June 30 of the
                  immediately preceding year, the Company or the Executive shall
                  have given notice that it or the Executive, as the case may
                  be, does not wish to have the Term extended and (B) subject to
                  the last sentence of Section 9, if, prior to a Change in
                  Control, the Executive ceases for any reason to be an employee
                  of the Company and any Subsidiary, thereupon without further
                  action the Term shall be deemed to have expired and this
                  Agreement will immediately terminate and be of no further
                  effect. For purposes of this Section 1(1), the Executive shall
                  not be deemed to have ceased to be an employee of the Company
                  and any Subsidiary by reason of the transfer of Executive's
                  employment between the Company and any Subsidiary, or among
                  any Subsidiaries.

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         (m)               "Termination Date" means the date on which the
                  Executive's employment is terminated (the effective date of
                  which shall be the date of termination, or such other date
                  that may be specified by the Executive if the termination is
                  pursuant to Section 3(b)).

          (n)              "Voting Stock" means securities entitled to vote
                  generally in the election of directors.

2.                Operation of Agreement. This Agreement will be effective and
         binding immediately upon its execution, but, anything in this Agreement
         to the contrary notwithstanding, except as provided in Sections 8 and
         9, this Agreement will not be operative unless and until a Change in
         Control occurs. Upon the occurrence of a Change in Control at any time
         during the Term, without further action, this Agreement shall become
         immediately operative.

3.                Termination Following a Change in Control. (a) In the event of
         the occurrence of a Change in Control, the Executive's employment may
         be terminated by the Company or a Subsidiary during the Severance
         Period and the Executive shall be entitled to the benefits provided by
         Section 4 unless such termination is the result of the occurrence of
         one or more of the following events:

                  (i)      The Executive's death;

                  (ii)     If the Executive becomes permanently disabled within
                           the meaning of, and begins actually to receive
                           disability benefits pursuant to, the long-term
                           disability plan in effect for, or applicable to,
                           Executive immediately prior to the Change in Control;
                           or

                  (iii)    Cause.

         If, during the Severance Period, the Executive's employment is
terminated by the Company or any Subsidiary other than pursuant to Section
3(a)(i), 3(a)(ii) or 3(a)(iii), the Executive will be entitled to the benefits
provided by Section 4 hereof.

         (b)               In the event of the occurrence of a Change in
                  Control, the Executive may terminate employment with the
                  Company and any Subsidiary during the Severance Period with
                  the right to severance compensation as provided in Section 4
                  upon the occurrence of one or more of the following events
                  (regardless of whether any other reason, other than Cause as
                  hereinabove provided, for such termination exists or has
                  occurred, including, without limitation, other employment):

                  (i)      Failure to elect or reelect or otherwise to maintain
                           the Executive in the office or the position, or a
                           substantially equivalent office or position, of or
                           with the Company and/or a Subsidiary (or any
                           successor thereto by operation of law of or
                           otherwise), as the case may be, which the Executive
                           held immediately prior to a Change in Control, or the
                           removal of the Executive as a director of the Company
                           and/or a Subsidiary (or any

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                           successor thereto) if the Executive shall have been a
                           director of the Company and/or a Subsidiary
                           immediately prior to the Change in Control;

                  (ii)     (A) A significant adverse change in the nature or
                           scope of the authorities, powers, functions,
                           responsibilities or duties attached to the position
                           with the Company and any Subsidiary which the
                           Executive held immediately prior to the Change in
                           Control, (B) a reduction in the aggregate of the
                           Executive's Base Pay received from the Company and
                           any Subsidiary or the Executive's Incentive Pay
                           opportunity from the Company or its Subsidiaries, or
                           (C) the termination or denial of the Executive's
                           rights to Employee Benefits or a reduction in the
                           scope or value thereof to a level that is
                           substantially lower in the aggregate from the level
                           in effect at the time of the Change in Control, any
                           of which is not remedied by the Company within 10
                           calendar days after receipt by the Company of written
                           notice from the Executive of such change, reduction,
                           denial or termination, as the case may be;

                  (iii)    The liquidation, dissolution, merger, consolidation
                           or reorganization of the Company or transfer of all
                           or substantially all of its business and/or assets,
                           unless the successor or successors (by liquidation,
                           merger, consolidation, reorganization, transfer or
                           otherwise) to which all or substantially all of its
                           business and/or assets have been transferred (by
                           operation of law or otherwise) assumed all duties and
                           obligations of the Company under this Agreement
                           pursuant to Section 12(a);

                  (iv)     The Company relocates its principal executive offices
                           (if such offices are the principal location of
                           Executive's work), or requires the Executive to have
                           his principal location of work changed, to any
                           location that, in either case, is in excess of 50
                           miles from the location thereof immediately prior to
                           the Change in Control, or requires the Executive to
                           travel away from his office in the course of
                           discharging his responsibilities or duties hereunder
                           at least 20% more (in terms of aggregate days in any
                           calendar year or in any calendar quarter when
                           annualized for purposes of comparison to any prior
                           year) than was required of Executive in any of the
                           three full years immediately prior to the Change in
                           Control without, in either case, his prior written
                           consent; or

                  (v)      Without limiting the generality or effect of the
                           foregoing, any material breach of this Agreement by
                           the Company or any successor thereto which is not
                           remedied by the Company within 10 calendar days after
                           receipt by the Company of written notice from the
                           Executive of such breach.

         (c)               Except as otherwise provided herein, a termination by
                  the Company pursuant to Section 3 (a) or by the Executive
                  pursuant to Section 3(b) will not affect any rights that the
                  Executive may have pursuant to any agreement, policy, plan,
                  program or arrangement of the Company or Subsidiary providing
                  Employee Benefits, which rights shall be governed by the terms
                  thereof, except for any

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                  rights to severance compensation to which Executive may be
                  entitled upon termination of employment pursuant to Paragraph
                  6(a)(iii) of the Executive's employment agreement, dated
                  December 9, 2002, which rights shall, during the Severance
                  Period, be superseded by this Agreement.

4.                Severance Compensation. (a) If, following the occurrence of a
         Change in Control, the Company or Subsidiary terminates the Executive's
         employment during the Severance Period other than pursuant to Section
         3(a)(i), 3(a)(ii) or 3(a)(iii), or if the Executive terminates his
         employment pursuant to Section 3(b), the Company shall pay to the
         Executive the amounts described in Annex A within five business days
         after the Termination Date and shall provide to the Executive the
         benefits described on Annex A for the periods described therein.

                  (b)      Without limiting the rights of the Executive at law
or in equity, in the event it is determined that the Company fails to make any
payment or provide any benefit required to be made or provided hereunder on a
timely basis, the Company shall pay interest on the amount or value thereof at
an annualized rate of interest equal to the so-called composite "prime rate" as
quoted from time to time during the relevant period in the The Wall Street
Journal, plus 4%. Any change in such prime rate shall be effective on and as of
the date of such change.

                  (c)      Notwithstanding any provision of this Agreement to
the contrary, the parties' respective rights and obligations under this Section
4 and under Sections 5, 7, 8 and the last sentence of Section 9 will survive any
termination or expiration of this Agreement or the termination of the
Executive's employment following a Change in Control for any reason whatsoever.

                  (d)      Notwithstanding any provision to the contrary in any
applicable plan, program or agreement, upon the occurrence of a Change in
Control, all equity incentive awards held by the Executive shall become fully
vested and all stock options held by the Executive shall become fully
exercisable.

5.                Limitation on Payments and Benefits. Notwithstanding any
         provision of this Agreement to the contrary, if any amount or benefit
         to be paid or provided under this Agreement would be an "Excess
         Parachute Payment," within the meaning of Section 280G of the Internal
         Revenue Code of 1986, as amended (the "Code"), or any successor
         provision thereto, but for the application of this sentence, then the
         payments and benefits to be paid or provided under this Agreement shall
         be reduced to the minimum extent necessary (but in no event to less
         than zero) so that no portion of any such payment or benefit, as so
         reduced, constitutes an Excess Parachute Payment; provided, however,
         that the foregoing reduction shall be made only if and to the extent
         that such reduction would result in an increase in the aggregate
         payment and benefits to be provided, determined on an after-tax basis
         (taking into account the excise tax imposed pursuant to Section 4999 of
         the Code, or any successor provision thereto, any tax imposed by any
         comparable provision of state law, and any applicable federal, state
         and local income taxes). The determination of whether any reduction in
         such payments or benefits to be provided under this Agreement or
         otherwise is required pursuant to the

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         preceding sentence shall be made at the expense of the Company, if
         requested by the Executive or the Company, by the Company's independent
         accountants. The fact that the Executive's right to payments or
         benefits may be reduced by reason of the limitations contained in this
         Section 5 shall not of itself limit or otherwise affect any other
         rights of the Executive other than pursuant to this Agreement. In the
         event that any payment or benefit intended to be provided under this
         Agreement or otherwise is required to be reduced pursuant to this
         Section 5, the Executive shall be entitled to designate the payments
         and/or benefits to be so reduced in order to give effect to this
         Section 5. The Company shall provide the Executive with all information
         reasonably requested by the Executive to permit the Executive to make
         such designation. In the event that the Executive fails to make such
         designation within 10 business days of the Termination Date, the
         Company may effect such reduction in any manner it deems appropriate.

6.                No Mitigation Obligation. The Company hereby acknowledges that
         it will be difficult and may be impossible for the Executive to find
         reasonably comparable employment following the Termination Date.
         Accordingly, the payment of the severance compensation by the Company
         to the Executive in accordance with the terms of this Agreement is
         hereby acknowledged by the Company to be reasonable, and the Executive
         will not be required to mitigate the amount of any payment provided for
         in this Agreement by seeking other employment or otherwise, nor will
         any profits, income, earnings or other benefits from any source
         whatsoever create any mitigation, offset, reduction or any other
         obligation on the part of the Executive hereunder or otherwise, except
         as expressly provided in the last sentence of Section 2 set forth on
         Annex A.

7.                Legal Fees and Expenses. It is the intent of the Company that
         the Executive not be required to incur legal fees and the related
         expenses associated with the interpretation, enforcement or defense of
         Executive's rights under this Agreement by litigation or otherwise
         because the cost and expense thereof would substantially detract from
         the benefits intended to be extended to the Executive hereunder.
         Accordingly, if the Executive reasonably believes that the Company has
         failed to comply with any of its obligations under this Agreement or in
         the event that the Company or any other person takes or threatens to
         take any action to declare this Agreement void or unenforceable, or
         institutes any litigation or other action or proceeding designed to
         deny, or to recover from, the Executive the benefits provided or
         intended to be provided to the Executive hereunder, subject to the
         other provisions of this Section 7, the Company irrevocably authorizes
         the Executive from time to time to retain counsel of Executive's
         choice, at the expense of the Company to the extent and as hereafter
         provided, to advise and represent the Executive in connection with any
         such interpretation, enforcement or defense, including, without
         limitation, the initiation or defense of any litigation or other legal
         action, whether by or against the Company or any director, officer,
         stockholder or other person affiliated with the Company, in any
         jurisdiction. Notwithstanding any existing or prior attorney-client
         relationship between the Company and such counsel, the Company
         irrevocably consents to the Executive's entering into an
         attorney-client relationship with such counsel, and in that connection
         the Company and the Executive agree that a confidential relationship
         shall exist between the Executive and such counsel. The Company will
         pay and be solely responsible for any and all attorneys' and related
         fees and expenses incurred by the Executive in connection with any of
         the foregoing, except

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         to the extent that the Executive fails to prevail on a material claim
         in any such proceeding described in this Section 7.

8.                Confidentiality. The Executive acknowledges that in the course
         of his employment by the Company, he will or may have access to and
         become informed of confidential or proprietary information (as defined
         in this Section 8) of the Company. The Executive hereby covenants and
         agrees that he will not, without the prior written consent of the
         Company, during the Term or thereafter disclose to any person not
         employed by the Company, or use in connection with engaging in
         competition with the Company, any confidential or proprietary
         information of the Company. For purposes of this Agreement, the term
         "confidential or proprietary information" will include all information
         of any nature and in any form that is owned by the Company and that is
         not publicly available (other than by Executive's breach of this
         Section 8) or generally known to persons engaged in businesses similar
         or related to those of the Company. Confidential or proprietary
         information will include, without limitation, the Company's financial
         matters, customers, employees, industry contracts, strategic business
         plans, product development (or other proprietary product data),
         marketing plans, and all other secrets and all other information of a
         confidential or proprietary nature. For purposes of the preceding two
         sentences, the term "Company" will also include any Subsidiary
         (collectively, the "Restricted Group"). The foregoing obligations
         imposed by this Section 8 will not apply (i) during the Term, in the
         course of the business of and for the benefit of the Company, (ii) if
         such confidential or proprietary information will have become, through
         no fault of the Executive, generally known to the public or (iii) if
         the Executive is required by law to make disclosure (after giving the
         Company notice and an opportunity to contest such requirement).

9.                Employment Rights. Nothing expressed or implied in this
         Agreement will create any right or duty on the part of the Company or
         the Executive to have the Executive remain in the employment of the
         Company or any Subsidiary prior to or following any Change in Control.
         Any termination of employment of the Executive or the removal of the
         Executive from the office or position in the Company or any Subsidiary
         that occurs (i) not more than 90 days prior to the date on which a
         Change in Control occurs, and (ii) following the commencement of any
         discussion with a third person that ultimately results in a Change in
         Control, shall be deemed to be a termination or removal of the
         Executive after a Change in Control for purposes of this Agreement.

10.               Post-termination Assistance. Executive shall provide such
         information and assistance to the Company as the Company may reasonably
         request, upon reasonable notice, in connection with any litigation in
         which it or any of its affiliates is or may become a party. The Company
         shall reimburse the Executive for any expenses, including travel
         expenses, incurred by the Executive in connection with providing such
         information and assistance.

11.               Withholding of Taxes. The Company may withhold from any
         amounts payable under this Agreement all federal, state, city or other
         taxes as the Company is required to withhold pursuant to any applicable
         law, regulation or ruling.

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12.               Successors and Binding Agreement. (a) The Company will require
         any successor (whether direct or indirect, by purchase, merger,
         consolidation, reorganization or otherwise) to all or substantially all
         of the business or assets of the Company, by agreement in form and
         substance reasonably satisfactory to the Executive, expressly to assume
         and agree to perform this Agreement in the same manner and to the same
         extent the Company would be required to perform if no such succession
         had taken place. This Agreement will be binding upon and inure to the
         benefit of the Company and any successor to the Company, including,
         without limitation, any persons acquiring directly or indirectly all or
         substantially all of the business or assets of the Company whether by
         purchase, merger, consolidation, reorganization or otherwise (and such
         successor shall thereafter be deemed the "Company" for the purposes of
         this Agreement), but will not otherwise be assignable, transferable or
         delegable by the Company.

                  (b)      This Agreement will inure to the benefit of and be
enforceable by the Executive's personal or legal representatives, executors,
administrators, successors, heirs, distributees and legatees.

                  (c)      This Agreement is personal in nature and neither of
the parties hereto shall, without the consent of the other, assign, transfer or
delegate this Agreement or any rights or obligations hereunder except as
expressly provided in Sections 12(a) and 12(b). Without limiting the generality
or effect of the foregoing, the Executive's right to receive payments hereunder
will not be assignable, transferable or delegable, whether by pledge, creation
of a security interest, or otherwise, other than by a transfer by Executive's
will or by the laws of descent and distribution and, in the event of any
attempted assignment or transfer contrary to this Section 12(c), the Company
shall have no liability to pay any amount so attempted to be assigned,
transferred or delegated.

13.               Notices. For all purposes of this Agreement, all
         communications, including, without limitation, notices, consents,
         requests or approvals, required or permitted to be given hereunder will
         be in writing and will be deemed to have been duly given when hand
         delivered or dispatched by electronic facsimile transmission (with
         receipt thereof orally confirmed), or five business days after having
         been mailed by United States registered or certified mail, return
         receipt requested, postage prepaid, or three business days after having
         been sent by a nationally recognized overnight courier service (such as
         Federal Express or UPS) addressed to the Company (to the attention of
         the Secretary of the Company) at its principal executive office and to
         the Executive at his principal residence, or to such other address as
         any party may have furnished to the other in writing and in accordance
         herewith, except that notices of changes of address shall be effective
         only upon receipt.

14.               Governing Law. The validity, interpretation, construction and
         performance of this Agreement will be governed by and construed in
         accordance with the substantive laws of the State of Delaware, without
         giving effect to the principles of conflict of laws of such State.

15.               Validity. If any provision of this Agreement or the
         application of any provision hereof to any person or circumstances is
         held invalid, unenforceable or otherwise illegal,

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         the remainder of this Agreement and the application of such provision
         to any other person or circumstances will not be affected, and the
         provision so held to be invalid, unenforceable or otherwise illegal
         will be reformed to the extent (and only to the extent) necessary to
         make it enforceable, valid or legal.

16.               Miscellaneous. No provision of this Agreement may be modified,
         waived or discharged unless such waiver, modification or discharge is
         agreed to in writing signed by the Executive and the Company. No waiver
         by either party hereto at any time of any breach by the other party
         hereto or compliance with any condition or provision of this Agreement
         to be performed by such other party will be deemed a waiver of similar
         or dissimilar provisions or conditions at the same or at any prior or
         subsequent time. No agreements or representations, oral or otherwise,
         expressed or implied with respect to the subject matter hereof have
         been made by either party which are not set forth expressly in this
         Agreement. References to Sections are to references to Sections of this
         Agreement.

17.               Counterparts. This Agreement may be executed in one or more
         counterparts, each of which shall be deemed to be an original but all
         of which together will constitute one and the same agreement.

         IN WITNESS WHEREOF, the parties have caused this Agreement to be duly
 executed and delivered as of the date first above written.

                                    LAIDLAW INC.

                                    /s/ Kevin Benson
                                    ------------------------------------------
                                    By: Kevin Benson
                                    Its: President and Chief Executive Officer

                                    /s/ Douglas A Carty
                                    ------------------------------------------
                                    Douglas A Carty

                                       11

<PAGE>

                                     Annex A

1.       The Company shall pay to the Executive a lump sum payment in an amount
         equal to two (2) times the sum of (A) Base Pay (at the highest rate in
         effect for any period prior to the Termination Date), plus (B)
         Incentive Pay (in an amount equal to not less than the higher of (x)
         the highest aggregate Incentive Pay earned in any fiscal year after the
         Change in Control or in any of the three fiscal years immediately
         preceding the year in which the Change in Control occurred or (y) the
         plan target for which the year in which the Change in Control
         occurred).

2.       The Company shall, for a period of twenty four (24) months following
         the Termination Date (the "Continuation Period"), arrange to provide
         the Executive with Employee Benefits that are welfare benefits (but not
         stock option, stock purchase, stock appreciation or similar
         compensatory benefits) substantially similar to those that the
         Executive was receiving or entitled to receive immediately prior to the
         Termination Date (or, if greater, immediately prior to the reduction,
         termination or denial described in Section 3(b)(ii)), except that the
         level of any such Employee Benefits to be provided to the Executive may
         be reduced in the event of a corresponding reduction generally
         applicable to all recipients of or participants in such Employee
         Benefits, which Continuation Period will be considered service with the
         Company for the purpose of determining service credits and benefits due
         and payable to the Executive under the Company's retirement income,
         supplemental executive retirement and other benefit plans of the
         Company applicable to the Executive, his dependents or his
         beneficiaries immediately prior to the Termination Date. Without
         otherwise limiting the purpose or effect of Section 5, Employee
         Benefits otherwise receivable by the Executive pursuant to this Section
         2 will be reduced to the extent comparable welfare benefits are
         actually received by the Executive from another employer during the
         Continuation Period following the Executive's Termination Date, and any
         such benefits actually received by the Executive shall be reported by
         the Executive to the Company.

3.       In addition to the retirement income, supplemental executive
         retirement, and other benefits to which Executive is entitled under the
         Retirement Plans, a lump sum payment in an amount equal to the
         actuarial equivalent of the excess of (x) the retirement pension and
         the medical, life and other benefits that would be payable to the
         Executive under the Retirement Plans if Executive continued to be
         employed through the Continuation Period given the Executive's Base Pay
         (as determined in Section 1) (without regard to any amendment to the
         Retirement Plans made subsequent to a Change in Control which adversely
         affects in any manner the computation of retirement or welfare benefits
         thereunder), over (y) the retirement pension and the medical, life and
         other benefits that the Executive is entitled to receive (either
         immediately or on a deferred basis) under the Retirement Plans. For
         purposes of this Section, "actuarial equivalent" shall be determined
         using the actuarial assumptions mandated under Section 417(e)(3) of the
         Code in effect for the month second preceding the date of payment and
         the Continuation Period will be considered service with the Company for
         the purpose of determining service credits and benefits due and payable
         to the Executive under the Company's retirement pension and medical,
         life and other benefit plans of the Company

                                       A-1

<PAGE>

         applicable to the Executive, his dependents or his beneficiaries
         immediately prior to the Termination Date.

4.       Reasonable outplacement services by a firm selected by the Executive,
         at the expense of the Company, in an amount up to $25,000.

5.       If the Termination Date occurs on or prior to the first anniversary of
         the date hereof, the Company shall reimburse the Executive for
         reasonable and actual relocation expenses to Canada (or a destination
         of the Executive's choice of equal or lesser cost), subject to the
         Company's relocation policy and guidelines as in effect from time to
         time.

                                       A-2