Charles River Laboratories International, Inc. is an American pharmaceutical and biotechnology contract research organisation headquartered in Wilmington, Massachusetts, United States. Founded in 1947, the company provides preclinical and clinical laboratory services for the development of new drugs, vaccines, and medical devices. Its operations span at least 20 countries, offering research models, safety assessment, and manufacturing support services to pharmaceutical, biotechnology, and government clients. Charles River Laboratories is considered one of the largest CROs globally, known for its role in toxicology studies, animal research models, and microbial testing services used in regulatory submissions to health authorities such as the U.S. Food and Drug Administration. The company has also been the subject of public scrutiny and regulatory attention over its use of laboratory animals, including dogs, primates, and horseshoe crabs. As of 2024, the company employs over 20,000 people worldwide and is publicly traded on the New York Stock Exchange under the ticker symbol CRL.