Investor Relations

WILMINGTON, Mass.--(BUSINESS WIRE)--May 21, 2003--Charles River Laboratories International, Inc. (NYSE:CRL), a leading provider of pre-clinical research products and services to pharmaceutical and biotechnology companies, announced that it has been ranked fourth overall in The Boston Globe 15th Annual Globe 100 listing of best-performing public companies in Massachusetts.

The Boston Globe evaluated the performance of the region's top public companies based on 2002 revenue growth, improvement in profit margin, and return on shareholders' equity. The data were compiled and analyzed by Compustat, a product of Standard & Poor's. To be considered for the rankings, companies must be headquartered in Massachusetts, been public for all of 2002, reported positive net income in both 2001 and 2002, and have a positive average of the current and year-ago equity.

In 2002, Charles River's revenues grew by almost 20 percent, and its earnings per diluted share by more than 50 percent. The world's leading provider of research models enhanced its core business segment with an international cooperative distribution agreement with The Jackson Laboratory. The completion of several facility expansions, including a new 70,000-square-foot building for breeding and housing genetically engineered animals, significantly increased capacity to offer animal support services. Charles River also further developed its portfolio of drug discovery and development testing services by acquiring Ireland-based Biological Laboratories Europe Ltd. ("BioLabs") and Springborn Laboratories in Ohio.

"Through strategic acquisitions and sound partnerships, we continue to position ourselves as the premiere provider of products and services needed to accelerate the drug development process," said James C. Foster, Charles River Chairman, President and Chief Executive Officer. "By offering pre-clinical outsourcing services in conjunction with our research models, Charles River gives customers the convenience of dealing with one partner for many of their drug discovery and development needs."

About Charles River Laboratories

Charles River Laboratories, based in Wilmington, Massachusetts, is a leading provider of critical research tools and integrated support services that enable innovative and efficient drug discovery and development. The Company is the global leader in providing the animal research models required in research and development for new drugs, devices and therapies. The Company also offers a broad and growing portfolio of biomedical products and services that enable customers to reduce cost, increase speed, and enhance productivity and effectiveness in drug discovery and development. Charles River's customer base spans over 50 countries, and includes all of the major pharmaceutical companies, biotechnology companies, and many leading hospitals and academic institutions. The Company operates 82 facilities in 16 countries worldwide. For more information, visit the Company's web site at www.criver.com.

    CONTACT: Charles River Laboratories
             Media Relations:
             Julie Palm, 978/658-6000
             jpalm@criver.com
             or
             Investor Relations:
             Susan E. Hardy, 978/658-6000
             shardy@criver.com

    SOURCE: Charles River Laboratories