US-Japan meetings on laboratory animal science have been held virtually every year since 1980 under the US-Japan Cooperative Program on Science and Technology. Over the years these meetings have resulted in a number of important documents including the Manual of Microbiologic of Monitoring of Laboratory Animals published in 1994 and the article Establishment and Preservation of Reference Inbred Strains of Rats for General Purposes published in 1991. In addition to these publications, these meetings have been instrumental in increasing awareness of the need for microbiologic monitoring of laboratory rodents and the need for genetic definition and monitoring of mice and rats.