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                                                                      Exhibit 10


                              EMPLOYMENT AGREEMENT

     THIS EMPLOYMENT AGREEMENT is made as of April 1, 1999 by and between IDEXX
Laboratories, Inc., a Delaware corporation (the "Company"), and Jeffrey J.
Langan (the "Executive").

     The Board of Directors of the Company (the "Board") has determined that it
is in the best interests of the Company and its shareholders to assure that the
Company will have the continued dedication of the Executive, notwithstanding the
possibility, threat or occurrence of a Change of Control (as defined below) of
the Company. The Board believes it is imperative to diminish the inevitable
distraction of the Executive by virtue of the personal uncertainties and risks
created by a pending or threatened Change of Control and to encourage the
Executive's full attention and dedication to the Company currently and in the
event of any threatened or pending Change of Control, and to provide the
Executive with compensation and benefits arrangements upon a Change of Control
which ensure that the compensation and benefits expectations of the Executive
will be satisfied and which are competitive with those of other corporations.
Therefore, in order to accomplish these objectives, the Board has caused the
Company to enter into this Agreement.

     NOW, THEREFORE, IT IS HEREBY AGREED AS FOLLOWS:

     1. Certain Definitions.
        -------------------

               (a) The "Effective Date" shall mean the first date during the
Change of Control Period (as defined in Section 1(b)) on which a Change of
Control (as defined in Section 2) occurs. Anything in this Agreement to the
contrary notwithstanding, if a Change of Control occurs and if the Executive's
employment with the Company is terminated prior to the date on which the Change
of Control occurs, and if it is reasonably demonstrated by the Executive that
such termination of employment (i) was at the request of a third party who has
taken steps reasonably calculated to effect a Change of Control or (ii)
otherwise arose in connection with or anticipation of a Change of Control, then
for all purposes of this Agreement the "Effective Date" shall mean the date
immediately prior to the date of such termination of employment.

               (b) The "Change of Control Period" shall mean the period
commencing on the date hereof and ending on the third anniversary of the date
hereof; provided, however, that commencing on the date one year after the date
hereof, and on each annual anniversary of such date (such date and each annual
anniversary thereof shall be hereinafter referred to as the "Renewal Date"),
unless previously terminated, the Change of Control Period shall be
automatically extended so as to terminate three years from such Renewal Date,
unless at least 120 days prior to the Renewal Date the Company shall give notice
to the Executive that the Change of Control Period shall not be so extended.


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     2. Change of Control. For the purpose of this Agreement, a "Change of
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Control" shall mean:

               (a) The acquisition by an individual, entity or group (within the
meaning of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934,
as amended (the "Exchange Act")) (a "Person") of beneficial ownership (within
the meaning of Rule 13d-3 promulgated under the Exchange Act) of 20% or more of
either (i) the then-outstanding shares of common stock of the Company (the
"Outstanding Company Common Stock") or (ii) the combined voting power of the
then-outstanding voting securities of the Company entitled to vote generally in
the election of directors (the "Outstanding Company Voting Securities");
provided, however, that for purposes of this subsection (a), the following
acquisitions shall not constitute a Change of Control: (i) any acquisition
directly from the Company, (ii) any acquisition by the Company, (iii) any
acquisition by any employee benefit plan (or related trust) sponsored or
maintained by the Company or any corporation controlled by the Company, or (iv)
any acquisition by any corporation pursuant to a transaction which satisfies the
criteria set forth in clauses (i), (ii) and (iii) of subsection (c) of this
Section 2; or

               (b) Individuals who, as of the date hereof, constitute the Board
(the "Incumbent Board") cease for any reason to constitute at least a majority
of the Board; provided, however, that any individual becoming a director
subsequently to the date hereof whose election, or nomination for election by
the Company's shareholders, was approved by a vote of at least a majority of the
directors then comprising the Incumbent Board 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 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; or

               (c) 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"), in each case, unless, following such
Business Combination, (i) all or substantially all of the individuals and
entities who were the beneficial owners, respectively, of the Outstanding
Company Common Stock and Outstanding Company Voting Securities immediately prior
to such Business Combination beneficially own, directly or indirectly, more than
60% of, respectively, 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 corporation resulting from such
Business Combination (which as used in this Section 2(c) shall include, without
limitation, a corporation 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 as their
ownership, immediately prior to such Business Combination of the Outstanding
Company Common Stock and Outstanding Company Voting Securities, as the case may
be, (ii) no Person (excluding any corporation resulting from such Business
Combination or any employee benefit plan (or related trust) of the Company or
such corporation resulting from such Business Combination) beneficially owns,
directly or indirectly, 20% or more of, respectively, the then outstanding
shares of common stock of the corporation resulting from such Business
Combination, or the combined voting power of the then-outstanding voting
securities of such corporation and (iii) at least half of the members of the
board of directors of the corporation resulting from such

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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

               (d) Approval by the shareholders of the Company of a complete
liquidation or dissolution of the Company.

     3. Employment Period. The Company hereby agrees to continue the Executive
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in its employ, and the Executive hereby agrees to remain in the employ of the
Company subject to the terms and conditions of this Agreement, for the period
commencing on the Effective Date and ending on the third anniversary of such
date (the "Employment Period"). Except as provided in Section 1(a), nothing in
this Agreement shall, prior to the Effective Date, impose upon the Company any
obligation to retain the Executive as an employee. In addition, nothing in this
Agreement shall restrict the Executive from terminating his employment with the
Company, and no such termination by the Executive shall be deemed a breach of
this Agreement.

     4. Terms of Employment.
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               (a) Position and Duties.
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                    (i) During the Employment Period, (A) the Executive's
position (including status, offices, titles and reporting requirements),
authority, duties and responsibilities shall be at least commensurate in all
material respects with the most significant of those held, exercised and
assigned at any time during the 120-day period immediately preceding the
Effective Date and (B) the Executive's services shall be performed at the
location where the Executive was employed immediately preceding the Effective
Date or any office or location less than 35 miles from such location.

                    (ii) During the Employment Period, and excluding any periods
of vacation and sick leave to which the Executive is entitled, the Executive
agrees to devote reasonable attention and time during normal business hours to
the business and affairs of the Company and, to the extent necessary to
discharge the responsibilities assigned to the Executive hereunder, to use the
Executive's reasonable best efforts to perform faithfully and efficiently such
responsibilities. During the Employment Period it shall not be a violation of
this Agreement for the Executive to (A) serve on corporate, civic or charitable
boards or committees, (B) deliver lectures, fulfill speaking engagements or
teach at educational institutions, and (C) manage personal investments, so long
as such activities do not significantly interfere with the performance of the
Executive's responsibilities as an employee of the Company in accordance with
this Agreement. It is expressly understood and agreed that to the extent that
any such activities have been conducted by the Executive prior to the Effective
Date, the continued conduct of such activities (or the conduct of activities
similar in nature and scope thereto) subsequent to the Effective Date shall not
thereafter be deemed to interfere with the performance of the Executive's
responsibilities to the Company.


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               (b) Compensation.
                   ------------

                    (i) Base Salary. During the Employment Period, the Executive
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shall receive an annual base salary ("Annual Base Salary"), which shall be paid
at a monthly rate, at least equal to twelve times the highest monthly base
salary paid or payable, including any base salary which has been earned but
deferred, to the Executive by the Company and its affiliated companies in
respect of the twelve-month period immediately preceding the month in which the
Effective Date occurs. During the Employment Period, the Annual Base Salary
shall be reviewed no more than 12 months after the last salary increase awarded
to the Executive prior to the Effective Date and thereafter at least annually.
Any increase in Annual Base Salary shall not serve to limit or reduce any other
obligation to the Executive under this Agreement. Annual Base Salary shall not
be reduced after any such increase and the term Annual Base Salary as utilized
in this Agreement shall refer to Annual Base Salary as so increased. As used in
this Agreement, the term "affiliated companies" shall include any company
controlled by, controlling or under common control with the Company.

                    (ii) Annual Bonus. In addition to Annual Base Salary, the
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Executive shall be entitled to receive such annual bonus as may be determined by
the Board of Directors, but in no event less than the annual bonus paid or
payable in respect of the full fiscal year immediately preceding the Effective
Date.

                    (iii) Incentive Plans. During the Employment Period, the
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Executive shall be entitled to participate in all incentive plans, practices,
policies and programs applicable generally to other peer Executives of the
Company and its affiliated companies, but in no event shall such plans,
practices, policies and programs provide the Executive with benefits which are
less favorable, in the aggregate, than the most favorable of such plans,
practices, policies and programs in effect for the Executive at any time during
the 120-day period immediately preceding the Effective Date or, if more
favorable to the Executive, those provided generally at any time after the
Effective Date to other peer executives of the Company and its affiliated
companies.

                    (iv) Welfare Benefit, Savings and Retirement Plans. During
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the Employment Period, the Executive and/or the Executive's family, as the case
may be, shall be eligible for participation in and shall receive all benefits
under welfare benefit, savings and retirement plans, practices, policies and
programs provided by the Company and its affiliated companies (including,
without limitation, medical, prescription, dental, disability, employee life,
group life, split-dollar life, accidental death and travel accident insurance
plans and programs) to the extent applicable generally to other peer executives
of the Company, but in no event shall such plans, practices, policies and
programs provide the Executive with benefits which are less favorable, in the
aggregate, than the most favorable of such plans, practices, policies and
programs in effect for the Executive at any time during the 120-day period
immediately preceding the Effective Date or, if more favorable to the Executive,
those provided generally at any time after the Effective Date to other peer
executives of the Company and its affiliated companies.


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                    (v) Expenses. During the Employment Period, the Executive
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shall be entitled to receive reimbursement for all reasonable expenses incurred
by the Executive in accordance with the policies, practices and procedures of
the Company in effect immediately prior to the Effective Date.

                    (vi) Vacation. During the Employment Period, the Executive
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shall be entitled to paid vacation in accordance with the plans, policies,
programs and practices of the Company and its affiliated companies, but in no
event shall such plans, practices, policies and programs provide the Executive
with benefits which are less favorable, in the aggregate, than the most
favorable of such plans, practices, policies and programs in effect for the
Executive at any time during the 120-day period immediately preceding the
Effective Date or, if more favorable to the Executive, those provided generally
at any time after the Effective Date to other peer executives of the Company and
its affiliated companies.

               (c) Options. Upon the occurrence of a Change of Control, all
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outstanding options to purchase shares of Common Stock held by the Executive
shall become immediately exercisable in full.

     5. Termination of Employment.
        -------------------------

               (a) Death or Disability. The Executive's employment shall
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terminate automatically upon the Executive's death during the Employment Period.
If the Company determines in good faith that the Disability of the Executive has
occurred during the Employment Period (pursuant to the definition of Disability
set forth below), it may give to the Executive written notice in accordance with
Section 12(b) of this Agreement of its intention to terminate the Executive's
employment. In such event, the Executive's employment with the Company shall
terminate effective on the 30th day after receipt of such notice by the
Executive (the "Disability Effective Date"), provided that, within the 30 days
after such receipt, the Executive shall not have returned to full-time
performance of the Executive's duties. For purposes of this Agreement,
"Disability" shall mean the absence of the Executive from the Executive's duties
with the Company on a full-time basis for 180 consecutive business days as a
result of incapacity due to mental or physical illness which is determined to be
total and permanent by a physician selected by the Company or its insurers and
acceptable to the Executive or the Executive's legal representative.

               (b) Cause. Subject to Section 5(d), the Company may terminate the
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Executive's employment during the Employment Period for Cause. For purposes of
this Agreement, "Cause" shall mean:

                    (i) the willful failure of the Executive to perform
substantially the Executive's duties with the Company (other than any such
failure resulting from incapacity due to physical or mental illness), which
failure is not cured within 30 days after a written demand for substantial
performance is delivered to the Executive by the Board which specifically
identifies the manner in which the Board believes that the Executive has not
substantially performed the Executive's duties, or


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                    (ii) the willful engaging by the Executive in illegal
conduct or gross misconduct which is materially and demonstrably injurious to
the Company.

     For purposes of this provision, no act or failure to act, on the part of
the Executive, shall be considered "willful" unless it is done, or omitted to be
done, by the Executive in bad faith or without reasonable belief that the
Executive's action or omission was in the best interests of the Company.

               (c) Good Reason. The Executive's employment may be terminated by
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the Executive for Good Reason. For purposes of this Agreement, "Good Reason"
shall mean:

                    (i) any failure by the Company to comply with and satisfy
Section 11(c) of this Agreement.

     For purposes of this Section 5(c), any good faith determination of "Good
Reason" made by the Executive shall be conclusive.

     Anything in this Agreement to the contrary notwithstanding, a termination
by the Executive for any reason or no reason during the 30-day period
immediately following the first twelve (12) months after the Effective Date
shall be deemed to be a termination for Good Reason for all purposes of this
Agreement.

               (d) Notice of Termination.
                   ---------------------

                    (i) Any termination by the Company for Cause, or by the
Executive for Good Reason, shall be effected by Notice of Termination to the
other party hereto given in accordance with Section 12(b) of this Agreement. For
purposes of this Agreement, a "Notice of Termination" means a written notice
which (i) indicates the specific termination provision in this Agreement relied
upon, (ii) to the extent applicable, sets forth in reasonable detail the facts
and circumstances claimed to provide a basis for termination of the Executive's
employment under the provision so indicated and (iii) if the Date of Termination
(as defined below) is other than the date of receipt of such notice, specifies
the termination date (which date shall be not more than thirty days after the
giving of such notice). The failure by the Executive or the Company to set forth
in the Notice of Termination any fact or circumstance which contributes to a
showing of Good Reason or Cause shall not waive any right of the Executive or
the Company, respectively, hereunder or preclude the Executive or the Company,
respectively, from asserting such fact or circumstances in enforcing the
Executive's or the Company's rights hereunder.

                    (ii) Any Notice of Termination for Cause must be given
within sixty (60) days of the Board learning of the event(s) or circumstance(s)
which the Board believes constitute(s) Cause. Prior to any Notice of Termination
for Cause being given (and prior to any termination for Cause being effective),
the Executive shall be entitled to a hearing before the Board at which he may,
at his election, be represented by counsel and at which he shall have a
reasonable opportunity to be heard. Such hearing shall be held on not less than
fifteen days prior written notice to the Executive stating the Board's intention
to terminate the Executive for Cause and stating in detail the particular
event(s) or circumstance(s) which the Board believes constitute(s) Cause for
termination.


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               (e) Date of Termination. "Date of Termination" means (i) if the
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Executive's employment is terminated by the Company for Cause, or by the
Executive for Good Reason, the date of receipt of the Notice of Termination or
any later date specified therein, as the case may be, subject, in the case of
termination by the Company, for Cause, to the Company's compliance with Section
5(d)(ii); (ii) if the Executive's employment is terminated by the Company other
than for Cause or Disability, the Date of Termination shall be the date on which
the Company notifies the Executive of such termination; and (iii) if the
Executive's employment is terminated by reason of death or Disability, the Date
of Termination shall be the date of death of the Executive or the Disability
Effective Date, as the case may be.

     6. Obligations of the Company Upon Termination.
        -------------------------------------------

               (a) Good Reason: Other Than for Cause, Death or Disability. If,
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during the Employment Period, the Company shall terminate the Executive's
employment other than for Cause or Disability or the Executive shall terminate
employment for Good Reason:

                    (i) the Company shall pay to the Executive in a lump sum in
cash within 30 days after the Date of Termination the aggregate of the following
amounts:

                         A. the sum of (1) the Executive's Annual Base Salary
     through the Date of Termination to the extent not theretofore paid, (2) the
     product of (x) the higher of (I) the highest annual cash bonus paid to the
     Executive in the last three fiscal years prior to the Effective Date and
     (II) the annual bonus paid or payable, including any bonus or portion
     thereof which has been earned but deferred (and annualized for any fiscal
     year consisting of less than twelve full months or during which the
     Executive was employed for less than twelve full months), for the most
     recently completed fiscal year during the Employment Period, if any (such
     higher amount being referred to as the "Highest Annual Bonus") and (y) a
     fraction, the numerator of which is the number of days in the current
     fiscal year through the Date of Termination, and the denominator of which
     is 365 and (3) any compensation previously deferred by the Executive
     (together with any accrued interest or earnings thereon) and any accrued
     vacation pay, in each case to the extent not theretofore paid (the sum of
     the amounts described in clauses (1), (2), and (3) shall be hereinafter
     referred to as the "Accrued Obligations"); and

                         B. the amount equal to the product of (1) three and (2)
     the sum of (x) the Executive's Annual Base Salary and (y) the Highest
     Annual Bonus.

               (ii) for 36 months after the Executive's Date of Termination, or
such longer period as may be provided by the terms of the appropriate plan,
program, practice or policy, the Company shall continue benefits to the
Executive and/or the Executive's family at least equal to those which would have
been provided to them in accordance with the plans, programs, practices and
policies described in Section 4(b)(iv) of this Agreement (excluding any savings
and/or retirement plans) if the Executive's employment had not been terminated
or, if more favorable to the Executive, as in effect generally at any time
thereafter with respect to other peer executives of the Company and its
affiliated companies and their families, provided, however, that if the
Executive becomes


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reemployed with another employer and is eligible to receive medical or other
welfare benefits under another employer-provided plan, the medical and other
welfare benefits described herein shall be secondary to those provided under
such other plan during such applicable period of eligibility. For purposes of
determining eligibility (but not the time of commencement of benefits) of the
Executive for retiree benefits pursuant to such plans, practices, programs and
policies, the Executive shall be considered to have remained employed until 36
months after the Date of Termination and to have retired on the last day of such
period; and

                    (iii) to the extent not theretofore paid or provided, the
Company shall timely pay or provide to the Executive any other amounts or
benefits required to be paid or provided or which the Executive is eligible to
receive under any plan, program, policy or practice or contract or agreement of
the Company and its affiliated companies (such other amounts and benefits shall
be hereinafter referred to as the "Other Benefits").

               (b) Death. If the Executive's employment is terminated by reason
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of the Executive's death during the Employment Period, this Agreement shall
terminate without further obligations to the Executive's legal representatives
under this Agreement, other than for payment of Accrued Obligations and the
timely payment or provision of Other Benefits. Accrued Obligations shall be paid
to the Executive's estate or beneficiary, as applicable, in a lump sum in cash
within 30 days of the Date of Termination.

               (c) Disability. If the Executive's employment is terminated by
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reason of the Executive's Disability during the Employment Period, this
Agreement shall terminate without further obligations to the Executive, other
than for payment of Accrued Obligations and the timely payment or provision of
Other Benefits. Accrued Obligations shall be paid to the Executive in a lump sum
in cash within 30 days of the Date of Termination.

               (d) Cause; Other than for Good Reason. If the Executive's
                   ---------------------------------
employment shall be terminated for Cause during the Employment Period, this
Agreement shall terminate without further obligations to the Executive other
than the obligation to pay to the Executive (x) his Annual Base Salary through
the Date of Termination, (y) the amount of any compensation previously deferred
by the Executive, and (z) Other Benefits, in each case to the extent theretofore
unpaid or not yet provided. If the Executive voluntarily terminates employment
during the Employment Period, excluding a termination for Good Reason, this
Agreement shall terminate without further obligations to the Executive, other
than for Accrued Obligations and the timely payment or provision of Other
Benefits. In such case, all Accrued Obligations shall be paid to the Executive
in a lump sum in cash within 30 days of the Date of Termination.

     7. Nonexclusivity of Rights. Nothing in this Agreement shall prevent or
        ------------------------
limit the Executive's continuing or future participation in any plan, program,
policy or practice provided by the Company or any of its affiliated companies
and for which the Executive may qualify, nor, subject to Section 12(f), shall
anything herein limit or otherwise affect such rights as the Executive may have
under any contract or agreement with the Company or any of its affiliated
companies. Amounts which are vested benefits or which the Executive is otherwise
entitled to receive under any plan, policy, practice or program of or any
contract or agreement with the Company or any of its affiliated companies at or
subsequent to the Date of Termination shall be payable in accordance


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with such plan, policy, practice or program or contract or agreement except as
explicitly modified by this Agreement.

     8. Full Settlement. The Company's obligation to make the payments provided
        ---------------
for in this Agreement and otherwise to perform its obligations hereunder shall
not be affected by any set-off, counterclaim, recoupment, defense or other
claim, right or action which the Company may have against the Executive (under
this Agreement or otherwise) or others. In no event shall the Executive be
obligated to seek other employment or take any other action by way of mitigation
of the amounts payable to the Executive under any of the provisions of this
Agreement and such amounts shall not be reduced whether or not the Executive
obtains other employment. The Company agrees to pay as incurred, to the full
extent permitted by law, all legal, accounting and other fees and expenses
(including, without limitation, of expert witnesses) which the Executive may
reasonably incur (i) as a result of any contest (regardless of the outcome
thereof) by the Company, the Executive or others of the validity or
enforceability of, or liability under, any provision of this Agreement or any
guarantee of performance thereof (including as a result of any contest by the
Executive about the amount of any payment pursuant to this Agreement), plus in
each case interest on any delayed payment at the applicable Federal rate
provided for in Section 7872(f)(2)(A) of the Internal Revenue Code of 1986, as
amended (the "Code"), (ii) in connection with the negotiation and preparation of
this Agreement and (iii) in connection with the Executive's performance of his
obligations under Section 9(c).

     9. Certain Additional Payments by the Company.
        ------------------------------------------

               (a) Anything in this Agreement to the contrary notwithstanding
and except as set forth below, in the event it shall be determined that any
payment or distribution by the Company to or for the benefit of the Executive
(whether paid or payable or distributed or distributable pursuant to the terms
of this Agreement or otherwise, but determined without regard to any additional
payments required under this Section 9)(a "Payment") would be subject to the
excise tax imposed by Section 4999 of the Code or any interest or penalties are
incurred by the Executive with respect to such excise tax (such excise tax,
together with any such interest and penalties, are hereinafter collectively
referred to as the "Excise Tax"), then the Executive shall be entitled to
receive an additional payment (a "Gross-Up Payment") in an amount such that
after payment by the Executive of all taxes (including any interest or penalties
imposed with respect to such taxes), including, without limitation, any income
taxes (and any interest and penalties imposed with respect thereto) and Excise
Tax imposed upon the Gross-Up Payment, the Executive retains an amount of the
Gross-Up Payment equal to the Excise Tax imposed upon the Payments.
Notwithstanding the foregoing provisions of this Section 9(a), if it shall be
determined that the Executive is entitled to a Gross-Up Payment, but that the
Executive, after taking into account the Payments and the Gross-Up Payment,
would not receive a net after-tax benefit of at least $50,000 (taking into
account both income taxes and any Excise Tax) as compared to the net after-tax
proceeds to the Executive resulting from an elimination of the Gross-Up Payment
and a reduction of the Payments, in the aggregate, to an amount (the "Reduced
Amount") such that the receipt of Payments would not give rise to any Excise
Tax, then no Gross-Up Payment shall be made to the Executive and the Payments,
in the aggregate, shall be reduced to the Reduced Amount.


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               (b) Subject to the provisions of Section 9(c), all determinations
required to be made under this Section 9, including whether and when a Gross-Up
Payment is required and the amount of such Gross-Up Payment and the assumptions
to be utilized in arriving at such determination, shall be made by Arthur
Andersen LLP or such other certified public accounting firm as may be designated
by the Executive (the "Accounting Firm") which shall provide detailed supporting
calculations both to the Company and the Executive within 15 business days of
the receipt of notice from the Executive that there has been a Payment, or such
earlier time as is requested by the Company. In the event that the Accounting
Firm is serving as accountant or auditor for the individual, entity or group
effecting the Change of Control, the Executive shall appoint another nationally
recognized accounting firm to make the determinations required hereunder (which
accounting firm shall then be referred to as the Accounting Firm hereunder). All
fees and expenses of the Accounting Firm shall be borne solely by the Company.
Any Gross-Up Payment, as determined pursuant to this Section 9, shall be paid by
the Company to the Executive within five days of the receipt of the Accounting
Firm's determination. Any determination by the Accounting Firm shall be binding
upon the Company and the Executive. As a result of the uncertainty in the
application of Section 4999 of the Code at the time of the initial determination
by the Accounting Firm hereunder, it is possible that Gross-Up Payments which
will not have been made by the Company should have been made ("Underpayment"),
consistent with the calculations required to be made hereunder. In the event
that the Company exhausts its remedies pursuant to Section 9(c) and the
Executive thereafter is required to make a payment of any Excise Tax, the
Accounting Firm shall determine the amount of the Underpayment that has occurred
and any such Underpayment shall be promptly paid by the Company to or for the
benefit of the Executive.

               (c) The Executive shall notify the Company in writing of any
claim by the Internal Revenue Service that, if successful, would require the
payment by the Company of the Gross-Up Payment. Such notification shall be given
as soon as practicable but no later than ten business days after the Executive
is informed in writing of such claim and shall apprise the Company of the nature
of such claim and the date on which such claim is requested to be paid. The
Executive shall not pay such claim prior to the expiration of the 30-day period
following the date on which it gives such notice to the Company (or such shorter
period ending on the date that any payment of taxes with respect to such claim
is due). If the Company notifies the Executive in writing prior to the
expiration of such period that it desires to contest such claim, the Executive
shall:

                    (i) give the Company any information reasonably requested by
the Company and available to the Executive relating to such claim,

                    (ii) take such action in connection with contesting such
claim as the Company shall reasonably request in writing from time to time,
including, without limitation, accepting legal representation with respect to
such claim by an attorney reasonably selected by the Company,

                    (iii) cooperate with the Company in good faith in order
effectively to contest such claim, and


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                    (iv) permit the Company to participate in any proceedings
relating to such claim; provided, however, that the Company shall bear and pay
directly all costs and expenses (including additional interest and penalties)
incurred in connection with such contest and shall indemnify and hold the
Executive harmless, on an after-tax basis, for any Excise Tax or income tax
(including interest and penalties with respect thereto) imposed as a result of
such representation and payment of costs and expenses. Without limitation on the
foregoing provisions of this Section 9(c), the Company shall control all
proceedings taken in connection with such contest and, at its sole option, may
pursue or forgo any and all administrative appeals, proceedings, hearings and
conferences with the taxing authority in respect of such claim and may, at its
sole option, either direct the Executive to pay the tax claimed and sue for a
refund or to contest the claim in any permissible manner, and the Executive
agrees to prosecute such contest to a determination before any administrative
tribunal, in a court of initial jurisdiction and in one or more appellate
courts, as the Company shall determine; provided, however, that if the Company
directs the Executive to pay such claim and sue for a refund, the Company shall
advance the amount of such payment to the Executive, on an interest-free basis
and shall indemnify and hold the Executive harmless, on an after-tax basis, from
any Excise Tax or income tax (including interest or penalties with respect
thereto) imposed with respect to such advance or with respect to any imputed
income with respect to such advance; and further provided that any extension of
the statute of limitations relating to payment of taxes for the taxable year of
the Executive with respect to which such contested amount is claimed to be due
is limited solely to such contested amount. Furthermore, the Company's control
of the contest shall be limited to issues with respect to which a Gross-Up
Payment would be payable hereunder and the Executive shall be entitled to settle
or contest, as the case may be, any other issue raised by the Internal Revenue
Service or other taxing authority.

               (d) If, after the receipt by the Executive of an amount advanced
by the Company pursuant to Section 9(c), the Executive becomes entitled to
receive any refund with respect to such claim, the Executive shall (subject to
the Company's complying with the requirements of Section 9(c)) promptly pay to
the Company the amount of such refund (together with any interest paid or
credited thereon after taxes applicable thereto). If, after the receipt by the
Executive of an amount advanced by the Company pursuant to Section 9(c), a
determination is made that the Executive shall not be entitled to any refund
with respect to such claim and the Company does not notify the Executive in
writing of its intent to contest such denial of refund prior to the expiration
of 30 days after such determination, then such advance shall be forgiven and
shall not be required to be repaid and the amount of such advance shall offset,
to the extent thereof, the amount of Gross-Up Payment required to be paid.

     10. Confidential Information. The Executive shall hold in a fiduciary
         ------------------------
capacity for the benefit of the Company all secret or confidential information,
knowledge or data relating to the Company or any of its affiliated companies,
and their respective businesses, which shall have been obtained by the Executive
during the Executive's employment by the Company or any of its affiliated
companies and which shall not be or become public knowledge (other than by acts
by the Executive or representatives of the Executive in violation of this
Agreement). After termination of the Executive's employment with the Company,
the Executive shall not, without the prior written consent of the Company or as
may otherwise be required by law or legal process, communicate or divulge any
such information, knowledge or data to anyone other than the Company and those
designated by it. In no event shall an asserted violation of the provisions of
this Section 10


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constitute a basis for deferring or withholding any amounts or benefits
otherwise payable or to be provided to the Executive under this Agreement.

     11. Successors.
         ----------

               (a) This Agreement is personal to the Executive and without the
prior written consent of the Company shall not be assignable by the Executive
otherwise than by will or the laws of descent and distribution. This Agreement
shall inure to the benefit of and be enforceable by the Executive's legal
representatives.

               (b) This Agreement shall inure to the benefit of and be binding
upon the Company and its successors and assigns.

               (c) The Company will require any successor (whether direct or
indirect, by purchase, merger, consolidation or otherwise) to all or
substantially all of the business and/or assets of the Company to assume
expressly and agree to perform this Agreement in the same manner and to the same
extent that the Company would be required to perform it if no such succession
had taken place. As used in this Agreement, "Company" shall mean the Company as
hereinbefore defined and any successor to its business and/or assets as
aforesaid.

     12. Miscellaneous.
         -------------

               (a) This Agreement shall be governed by and construed in
accordance with the laws of the State of Delaware, without reference to
principles of conflict of laws. The captions of this Agreement are not part of
the provisions hereof and shall have no force or effect. This Agreement may not
be amended or modified otherwise than by a written agreement executed by the
parties hereto or their respective successors and legal representatives.

               (b) All notices and other communications hereunder shall be in
writing and shall be given by hand delivery to the other party or by registered
or certified mail, return receipt requested, postage prepaid, addressed as
follows:

     If to the Executive:
     -------------------

     Jeffrey J. Langan, President and CEO
     IDEXX Laboratories, Inc.
     One Idexx Drive
     Westbrook, ME 04092

     If to the Company:
     -----------------

     IDEXX Laboratories, Inc.
     One Idexx Drive
     Westbrook, ME 04092
     Attention:  Chairman of Compensation Committee


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or to such other address as either party shall have furnished to the other in
writing in accordance herewith. Notice and communications shall be effective
when actually received by the addressee.

               (c) The invalidity or unenforceability of any provision of this
Agreement shall not affect the validity or enforceability of any other provision
of this Agreement.

               (d) The Company may withhold from any amounts payable under this
Agreement such Federal, state, local or foreign taxes as shall be required to be
withheld pursuant to any applicable law or regulation.

               (e) The Executive's or the Company's failure to insist upon
strict compliance with any provision of this Agreement or the failure to assert
any right the Executive or the Company may have hereunder, including, without
limitation the right of the Executive to terminate employment for Good Reason
pursuant to Section 5(c) of this Agreement, shall not be deemed to be a waiver
of such provision or right or any other provision or right of this Agreement.

               (f) The Executive and the Company acknowledge that, except as may
otherwise be provided under any other written agreement between the Executive
and the Company, the employment of the Executive by the Company is "at will"
and, subject to Section 1(a) hereof, prior to the Effective Date, the
Executive's employment and/or this Agreement may be terminated by either the
Executive or the Company, by written notice to the other, at any time prior to
the Effective Date, in which case the Executive shall have no further rights or
obligations under this Agreement. From and after the Effective Date this
Agreement shall supersede any other agreement between the parties with respect
to the subject matter hereof.

               (g) Any dispute or controversy arising under or in connection
with this Agreement shall be settled exclusively by arbitration, conducted
before a panel of three arbitrators in Portland, Maine, in accordance with the
rules of the American Arbitration Association then in effect. Judgment may be
entered on the arbitrator's award in any court of competent jurisdiction.

     IN WITNESS WHEREOF, the Executive has hereunto set the Executive's hand
and, pursuant to the authorization from its Board of Directors, the Company has
caused these presents to be executed in its name on its behalf, all as of the
day and year first above written.


                                             /s/ Jeffrey J. Langan
                                             ----------------------------
                                             Jeffrey J. Langan

                                             IDEXX Laboratories, Inc.

                                             By:

                                             /s/ Richard B. Thorp   
                                             ----------------------------
                                             Its: General Counsel and Secretary








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