A breed standard (also called bench standard or the standard) in the dog fancy is a set of guidelines covering specific externally observable qualities such as appearance, movement, and temperament for that dog breed. Breed standards are not scientific documents, but are written for each breed by clubs of hobbyists called breed clubs for their own specific requirements. Details and definitions within breed standards for a specific dog breed may vary from breed club to breed club and from country to country. Dog breed standards are similar in form and function to breed standards for other domesticated animals.
The breed standard for each breed of dog is distinct, giving a detailed "word picture" of the appearance and behaviour of an idealized dog of that breed. Included in the breed standard description are externally observable aspects of appearance and behaviour that are considered by the breed club to be the most important for the breed, and externally observable details of appearance or temperament that are considered by the breed club to be unacceptable (called faults). In addition most breed standards include an historical section, describing the place of origin and the original work done by the breed or its ancestor types.
However, breed standards do not include testing requirements for health, requirements for genetic testing, or requirements for specific types of training or work; breed standards are only intended to describe the breed's externally observable qualities. Breed clubs often make other requirements for health testing or work testing, but these are not covered in the breed standard itself.
The basis of judging in conformation dog shows is breed type, the whole of the characteristics that are typical of a breed. Breed type is outlined in the written breed standard for each breed, and the judge looks at the entered dogs for the ones that most perfectly resemble the judge's mental image of ideal breed type. Dogs are judged against the judge's mental ideal, not against each other. The goal of the conformation show is to identify breeding stock for the breed, and the breed standard is "the standard or model which breeders endeavour to achieve." Conformation shows are not intended for the examination of the entered dogs for fitness for purpose (such as hunting skill in a dog traditionally used for hunting), and while dogs may be excused by a judge for obvious lameness or illness, the dogs are not tested in the ring for genetic health or examined for the general health of the animal beyond externally observable appearance and behaviour as described in the breed standard.