Dog breeding is the vocation of mating carefully selected specimens to produce specific qualities and characteristics.At its best, breeding is a blend of science and art. The skilled breeder has knowledge of canine genetics and health, and the purpose for which his dogs will be used.At worst, breeding can be a slipshod enterprise in which the major concern is profit, with little regard to the health and welfare of the dogs involved. Breeding is often done by so-called ‘backyard breeders’ (the pejorative term for random or ignorant breeding conducted on a small scale), and ‘puppy mills’ or ‘puppy farms’ (larger businesses). It must be pointed out, however, that many excellent breeders run small-scale programs in their homes, barns, or back yards, and there are profitable large-scale operations run with knowledgeable staff and superlative veterinary care, so size and motive alone are not indicative of the quality of the breeding program.