LETTER AGREEMENT

Published on March 27, 1998


Exhibit 10.7



November 24, 1997 PERSONAL AND CONFIDENTIAL

Jeffrey J. Langan
23 Stonymeade Way
Acton, Mass. 01720

Dear Jeff:

We are very enthusiastic about having you join our management team as President
and Chief Operating Officer as we continue to pursue significant growth
opportunities at IDEXX. The purpose of this letter is to confirm key elements of
an employment offer. This letter will supersede our letter of October 29, 1997.

1. TITLE AND RESPONSIBILITIES

You will join IDEXX as President and Chief Operating Officer. This job carries
responsibility for most aspects of the management of IDEXX. This would include
management of our long range planning and budgeting processes, achievement of
key operating goals, enhancement of our staffing, training and development
efforts to meet worldclass standards, and reinforcement of our mission, values
and principles as we collectively build one of the world's great companies.

2. COMPENSATION

$300,000 annualized base compensation, plus participation in annual senior
management cash performance bonus programs with a expectation of a cash bonus of
50% of base compensation if personal and corporate goals are met. Performance
reviews with consideration of merit increases are performed annually on a
calendar year basis.

3. IDEXX RETIREMENT AND INCENTIVE SAVINGS PROGRAM

Eligible for enrollment in our 401K plan after 6 months employment prior to
quarterly enrollment dates.



4. IDEXX EMPLOYEE STOCK PURCHASE PROGRAM

Eligible for enrollment in the Plan after 6 months employment prior to twice
annual enrollment dates in January and July. The purpose of this program is to
create opportunities to purchase IDEXX stock on favorable terms.

5. MEDICAL BENEFITS

Contributory medical programs available to you and your family effective on the
first of the month following 30 days of employment.

6. INSURANCE

Life insurance at twice your annual salary. Long term disability at 70% salary
protection after a 90 day absence.

7. VACATION

Four weeks per year.

8. INCENTIVE STOCK OPTIONS

Option to purchase 250,000 shares of IDEXX common stock subject to vesting over
five years and exercisable over 10 years. These options are granted by the IDEXX
Board of Directors at the fair market value at the time of the grant and are
subject to the terms of the IDEXX Incentive Stock Option Grant Agreement and the
Company's incentive stock option plan. It has been customary in the past to make
additional annual grants to senior staff based on performance, and I would
anticipate annual option grants for up to 100,000 shares assuming that
performance goals are met - although any grant following your first full year at
IDEXX will be reduced by 50,000 shares due to the magnitude of this initial
grant.

9. RELOCATION

We expect you to relocate to Maine in mid-1998, and to work at our Westbrook
headquarters in the meantime. Reimbursement for relocation expenses will be
based on IDEXX relocation expense policies which we will provide to you, but
reimbursement would not exceed $50,000.

10. SIGNING BONUS

We will pay you a signing bonus of $100,000 in two parts: 1) $50,000 on February
1, 1998; and 2) $50,000 upon relocation of your family to Maine.



11. SEVERANCE TERMS

Should you be terminated without cause prior to January 1, 2000, IDEXX will
continue to pay your salary for one year at your then existing rate, and you
will continue to receive normal benefits during this period.

12. BOARD OF DIRECTORS

Per our discussions, you will be considered for election to the IDEXX Board of
Directors upon your acceptance of this offer. I believe that you would make a
very strong contribution to the Board.

13. OTHER TERMS

IDEXX Non-Compete and Invention/Non-Disclosure Agreements describe important
terms of employment at IDEXX and must be executed upon commencement of
employment. Additionally, we expect employment to begin by December 1, 1997.

Please re-confirm agreement with the terms of this offer by co-signing this
letter. On behalf of all of my colleagues, let me again say that we look forward
to a long and very rewarding relationship.



Sincerely,

/s/ David E. Shaw

David E. Shaw, Chairman
Chief Executive Officer



ACCEPTED:


/s/ Jeffrey Langan 11/24/97
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Jeffrey Langan Date