Appearance
Exact standards for the breed vary by country and organization, but the following criteria are generally part of the definition. The German Shepherd Dog is a large and strong dog, typically between 75 and 110lbs, but have been known to reach 130lbs. The height for males is typically 24-26in; for females it is 22-24in.The fur is a double-coat (under coat and outer coat). While some organizations accept long-haired German Shepherds, short-haired dogs are typically (and historically) preferred. There are many color variations. For conformation-line dogs, the most common ones are black-and-tan and black-and-red. Combinations containing very light hues such as cream are typically considered faulty. All-black is usually, but not always, accepted. A white German Shepherd is automatically disqualified from entering the show ring. Working-line dogs are typically sable, black-and-tan or black-and-brown. There are several different color-marking patterns. For conformation-line dogs, the "saddle" marking is probably the most well-known. This consists of a large black patch on the upper and mid back, extending partway down the dog's sides. The "sable" marking, which consists of one color with randomly-sized and -shaped patches or swaths of different-colored hair mixed in, is typical for working-line dogs. Some sable-pattern dogs have three colors in their coat; this is called agouti. The other popular marking is called "bi-color", and consists of a dog that is all one color (typically black) save for differently-colored paws and lower legs, and sometimes a swath on the belly.

German Shepherds are easily identifiable by their large head, ears which stand straight up, wedge-shaped muzzle and compact legs. They also have a distinctive gait, as well as other breed-specific features. Disqualifications for conformation-line dogs include white nails, a nose which isn't all-black, a muzzle which isn't predominantly black, non-erect ears, and very light-toned eyes.

Characteristics
German Shepherds are highly intelligent and agile dogs, with a strong work drive. They are often deployed in various roles such as police, guarding, search an rescue, therapy, service-dog, and in the military applications. German Shepherds are sparingly bred, by the efforts of a great few, for work function ("working line") as was originally intended by the breed inventor Max von Stephanitz. Most often they are bred to conform to breed appearance standards ("conformation line"). Though Max von Stephanitz distinctly stated, "Our shepherd dog is a service dog, and he must only be bred as a service dog. He must only be judged as a service dog. With service dogs, suitability ranks higher than beauty." He is also quoted as saying, "The most striking features of the correctly bred German Shepherd are firmness of nerves, attentiveness, unshockability, tractability, watchfulness, reliability and incorruptibility together with courage, tenacity and hardness." Max particularly pleads to champions of the breed to, "Take this trouble for me: Make sure my shepherd dog remains a working dog, for I have struggled all my life long for that aim."

Conformation line dogs are bred to proper physical appearance primarily and minimal working instincts (herding, prey drive, etc.) They are specifically bred to conform to the published breed standards for appearance, and health. Because they are bred for Conformation line dogs are often found as pets, in breeder environments, and in competition. Due to the nature of the Conformation ring, traits are lost to the breed decreasing its truest character and taking the "GSD" further from its original purpose. Working line German Shepherds are typically excluded from the show ring as most don't conform to the highest levels of the breed standard for physical appearance. These dogs are bred to have an enduring work drive, and unwavering obedience. Of critical importance is the dog's ability to distinguish what constitutes a threat and what does not constitute a threat. Dogs that cannot make that distinction are eliminated from police and military programs. Extremely well-suited for police and military work, these dogs are also suitable as pets for home environments, though for owners should be familiar with their dog's abilities and needs. Working line dogs are employed in many police departments and government organizations such as the ATF, the U.S. Marshals and Customs.

Temperament
The breed has a personality marked by direct, fearless willingness to protect what it considers its "den" (i.e. house, car, and property in a home situation) and "pack" (i.e. human family in a home situation). It is poised, but when the occasion demands, eager and alert; both fit and willing to serve in its capacity as a companion, watchdog, guide dog for people who are blind, herding dog, or guardian, whichever the circumstances may demand. Proper socialization as a puppy is one of the two key factors which determines what a dog's temperament will be as an adult. Genetics is the other. They go hand-in-hand; a dog with certain genetics cannot be trained to be stable and friendly, and by the same token the genetics most fit for training are meaningless if the dog is not well-socialized as a puppy. The "ideal" German Shepherd should be alert and fearless in defense of its den and pack, but loving and non-aggressive within the home environment.
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