Charles River Laboratories International, Inc., an early-stage contract research company, provides drug discovery and development services worldwide. It operates through three segments: Research Models and Services (RMS), Discovery and Safety Assessment (DSA), and Manufacturing Support (Manufacturing). The RMS segment produces and sells research model strains primarily genetically and microbiologically defined purpose-bred rats and mice for use by researchers. This segment also provides a range of services to assist its clients in supporting the use of research models in research and screening preclinical drug candidates comprising genetically engineered models and services, insourcing solutions, and research animal diagnostic services. The DSA segment offers early and in vivo discovery services for identification of a druggable target through delivery of preclinical drug and therapeutic candidates ready for safety assessment; and safety assessment services, which comprise bioanalysis, pharmacokinetics, drug metabolism, toxicology, and pathology services. The Manufacturing segment provides in vitro methods for conventional and rapid quality control testing of sterile and non-sterile biopharmaceuticals, and consumer products. This segment also offers specialized testing of biologics and devices that are outsourced by pharmaceutical and biotechnology companies; and avian vaccine services that provide specific-pathogen-free fertile chicken eggs and chickens used in the manufacture of live viruses. The company serves pharmaceutical and biotechnology companies, contract research organizations, agricultural and chemical companies, life science and veterinary medicine companies, contract manufacturing organizations, medical device companies, diagnostic and other commercial entities, hospitals, academic institutions, and government agencies. Charles River Laboratories International, Inc. was founded in 1947 and is headquartered in Wilmington, Massachusetts.