Design of laboratory animal facilities must be functional. Accordingly, the designer should be aware of the complex nature of animal research and specifically the type of animal research which will be conducted in a new facility. The building of animal-care facilities in research institutions requires special knowledge in laboratory animal medicine, animal husbandry, biomedical research, and architecture. A major concern should be accessibility of the facility by investigators and reasonable proximity to laboratory areas. Six general floor plans for housing laboratory animals are discussed. (RH)