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                                                                    Exhibit 10.5


                       MID-TERM INCENTIVE PROGRAM OVERVIEW


INTRODUCTION

The Mid-Term Incentive ("MTI") Program for Officers and senior managers of
Charles River Laboratories International, Inc. and its affiliated divisions (the
"Program") is designed to provide mid-term financial incentives to those
executives, senior managers, and key employees who are expected to contribute
significantly to the future growth and success of Charles River. The Program is
also intended to complement Charles River's annual stock option award program,
and to more closely align the performance objectives of participants with
Charles River's ongoing 3-year Strategic Plan objectives. The Program is
specifically intended to attract and retain talented individuals with desired
skills in an increasingly competitive labor market. Annual awards are made to
eligible participants through the execution of a Mid-Term Performance Units
Agreement ("MTI Agreement") between Charles River and the participant.

THE PROGRAM

     o    ELIGIBILITY

Participation in the Program for the current year (FY2004) is limited to
employees in Charles River Salary Grades 92 and higher (or, in the case of
recent acquisitions, salary grade equivalents). Eligible employees are entitled
to participate on a global basis, and must be actively employed by the company
at the time annual awards are made under the MTI Program in order to be eligible
for an award during that year. Charles River's President & CEO has the right to
exclude otherwise qualified employees from the Program if they are eligible for
alternate forms of incentive compensation (e.g., participation in a
post-acquisition earn-out).

     o    BASIC PROGRAM DESIGN

Each participant's performance is measured against financial or other approved
objectives established for the corporation as part of its 3-year Strategic Plan.
Corporate revenue and operating income objectives are typically used and are
weighted equally to ensure that incentives are appropriately aligned with
revenue growth and profitability objectives. Financial performance measures for
each award year are taken directly from the 3-year Strategic Plan that commences
that year, following review and approval by the Board of Directors in
conjunction with the annual Strategic Planning process and, as required, by the
Compensation Committee of the Board.

Incentive awards payable under the Program are determined by multiplying the
participant's Unit Award by his or her overall MTI Award Percentage (see below).


                                                                  April 15, 2004
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BONUS CALCULATIONS

Each participant in the MTI Program is awarded a certain number of Performance
Units following approval by the Compensation Committee. At the conclusion of the
3-year Strategic Plan period referenced in the MTI Agreement, the corporation's
performance against sales and operating income objectives is evaluated using a
matrix attached to the participant's MTI Agreement. The percentage payout
yielded by this matrix determines a participant's MTI Award Percentage.
Depending on performance, the number of units will be adjusted by the MTI Award
Percentage per the terms of his/her MTI Agreement. Adjusted unit awards can
range from zero to 200% of target.

If the unit award adjustment results in the award of performance units, within
sixty (60) days of the conclusion of the 3-year performance period, the
participant will receive:

     1.   A cash payment in a gross amount equal to 40% of the then-current
          aggregate value of the award, less appropriate deductions; and

     2.   A restricted stock award equal to 60% of the then-current aggregate
          value of the award, which will vest in equal installments over two
          years from the date the 3-year performance period concludes.

ATTACHMENT I to this Overview provides an example of how an award would be
calculated and paid to an MTI Program participant.

This Overview is intended to provide only a brief summary of some of the
significant features of the MTI Program and is not intended to fully summarize
your award agreement. You should read your specific Mid-Term Performance Units
Agreement in its entirety to ensure that you are familiar with and understand
the terms of your award.

If you have any questions regarding the MTI Program, please contact the
Sr. Vice President, Human Resources & Administration.


                                                                  April 15, 2004