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                                                                   EXHIBIT 10.1

                            IDEXX LABORATORIES, INC.

                            1999 DIRECTOR STOCK PLAN

                            (AS OF FEBRUARY 17, 1999)

     1.   PURPOSE

          The purpose of this 1999 Director Stock Plan (the "Plan") of IDEXX
Laboratories, Inc. (the "Company") is to encourage ownership in the Company by
outside directors of the Company whose continued services are considered
essential to the Company's future progress and to provide them with a further
incentive to remain as directors of the Company.

     2.   ADMINISTRATION

          The Board of Directors shall supervise and administer the Plan. Grants
of stock awards under the Plan and the amount and nature of the awards to be
granted shall be automatic in accordance with Section 5. However, all questions
of interpretation of the Plan or of any awards issued under it shall be
determined by the Board of Directors and such determination shall be final and
binding upon all persons having an interest in the Plan.

     3.   PARTICIPATION IN THE PLAN

          Directors of the Company who are not employees of the Company or any
subsidiary of the Company shall be eligible to participate in the Plan.

     4.   STOCK SUBJECT TO THE PLAN

          The maximum number of shares which may be issued under the Plan shall
be 80,000 shares of the Company's Common Stock, par value $.10 per share
("Common Stock"), subject to adjustment as provided in Section 8 of the Plan.
Shares of Common Stock issued under the Plan may consist in whole or in part of
authorized but unissued shares or treasury shares.

     5.   DELIVERY AND TRANSFERABILITY OF AWARDS

          (a) GRANT DATES AND AMOUNT. Following approval of the Plan by the
stockholders of the Company, upon the date of each annual meeting of
stockholders, including the date of the annual meeting of stockholders at which
the Plan is approved and adopted, the Company shall award to each eligible
director continuing in office after, or elected at, such meeting 2,000 shares of
Common Stock. In addition, in the case of any eligible director who is elected
other than at an annual meeting, the Company shall award to such director upon
his or her election the number of shares of Common Stock determined by the
following formula:

    2,000 x (365 less the number of days elapsed since last annual meeting)
             -------------------------------------------------------------
                                       365


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          (b) CONSIDERATION. To the extent required by Delaware law, the Board
of Directors may require a recipient of shares of Common Stock under the Plan to
pay an amount equal to the par value per share for each share of Common Stock
received under the Plan.

          (c) REGISTRATION OF SHARES. Common Stock to be delivered to an
eligible director under the Plan will be registered in the name of the director.

          (d) ASSIGNMENTS. The rights and benefits under the Plan may not be
assigned.

          (e) CONDITIONS ON DELIVERY OF STOCK. The Company will not be obligated
to deliver any shares of Common Stock pursuant to the Plan until (i) in the
opinion of the Company's counsel, all other legal matters in connection with the
issuance and delivery of such shares have been satisfied, including any
applicable securities laws and any applicable stock exchange or stock market
rules and regulations, and (ii) the recipient of such shares has executed and
delivered to the Company such representations or agreements as the Company may
consider appropriate to satisfy the requirements of any applicable laws, rules
or regulations.

     6.   TIME FOR GRANTING AWARDS

          All awards for shares subject to the Plan shall be granted, if at all,
not later than the fifth annual meeting of stockholders after the meeting of
stockholders at which the Plan is approved by the Company's stockholders.

     7.   NO RIGHT TO CONTINUE AS A DIRECTOR.

          Neither the Plan, nor the granting of an award nor any other action
taken pursuant to the Plan, shall constitute or be evidence of any agreement or
understanding, express or implied, that a director will hold office with the
Company for any period of time.

     8.   CHANGES IN COMMON STOCK.

          If the outstanding shares of Common Stock are increased, decreased or
exchanged for a different number or kind of shares or other securities, or if
additional shares or new or different shares or other securities are distributed
with respect to such shares of Common Stock or other securities, through merger,
consolidation, sale of all or substantially all of the assets of the Company,
reorganization, recapitalization, reclassification, stock dividend, stock split,
reverse stock split or other distribution with respect to such shares of Common
Stock, or other securities, an appropriate and proportionate adjustment will be
made in the maximum number and kind of shares reserved for issuance under the
Plan and in the number and kind of shares awardable under the Plan pursuant to
Section 5(a) after the date of such event.


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     9.   AMENDMENT OF THE PLAN

          The Board of Directors may suspend or discontinue the Plan or review
or amend it in any respect whatsoever; provided, however, that without approval
of the stockholders of the Company no revision or amendment shall change the
number of shares subject to the Plan (except as provided in Section 8), change
the designation of the class of directors eligible to receive awards, or
otherwise materially increase the benefits accruing to directors under the Plan.

     10.  NOTICE

          Any written notice to the Company required by any of the provisions of
the Plan shall be addressed to the Treasurer of the Company and shall become
effective when it is received.

     11.  GOVERNING LAW

          The Plan and all determinations made and actions taken pursuant hereto
shall be governed by the laws of the State of Delaware.

     Approved by the Board of Directors on February 17, 1999.

     Approved by the stockholders on May 19, 1999.


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