In November 1991 the UC Center for Animal Alternatives was established within the nine campuses of the University of California. It is sited at the School of Veterinary Medicine on the Davis campus and is headed by Dr Lynette Hart. The stated aim of the Center for Animal Alternatives (CAA) is to build on the concept of the Three Rs (replacement, reduction and refinement) of Russell and Burch but, as replacement and reduction are being widely tackled in several other places, to concentrate on refinement factors which may affect the well-being of the animals being used by man.