CORPORATE PRESS RELEASE

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           CHARLES RIVER LABORATORIES ANNOUNCES $150 MILLION OFFERING
                        OF SENIOR CONVERTIBLE DEBENTURES

         WILMINGTON, MASS.; JANUARY 15, 2002: Charles River Laboratories
International, Inc. (NYSE: CRL) today announced its intention, subject to market
and other conditions, to offer in a private placement approximately $150 million
in Senior Convertible Debentures. The Debentures, due in 2022, will be
convertible into shares of Charles River's common stock. Charles River has
granted the initial purchasers of the Debentures an option to purchase up to an
additional $25 million principal amount of Debentures, exercisable within 13
days of the initial offering. Charles River intends to use the net proceeds from
the Debenture offering to retire its wholly-owned subsidiary's (Charles River
Laboratories, Inc.) $79.7 million aggregate principal amount of 13.5% Senior
Subordinated Notes due 2009, through a tender offer and consent solicitation,
and for general corporate purposes. The offering is being made only to qualified
institutional buyers in accordance with Rule 144A of the Securities Act of 1933.

         Neither the Debentures nor the common stock issuable upon conversion of
the Debentures have been registered under the Securities Act of 1933, or any
state securities laws. Unless so registered, the Debentures and the common stock
issuable upon conversion of the Debentures may not be offered or sold in the
United States absent an exemption from, or in a transaction not subject to, the
registration requirements of the Securities Act and any applicable state
securities laws. This announcement is neither an offer to sell nor a
solicitation of an offer to buy any of these securities.