Seeing eye dog

Guide dogs, (also known as service animals or assistance animals), are assistance dogs trained to lead blind and visually impaired people around obstacles.

Although the dogs can be trained to navigate various obstacles, lots of them are (red–green) color blind and are not capable of interpreting street signs. The human does the directing, based on skills acquired through previous mobility training. The handler might be likened to an aircraft's navigator, who must know how to get from one place to another, and the dog is the pilot, who gets them there safely.

In several countries, guide dogs, along with most service and hearing dogs, are exempt from regulations against the presence of animals in places such as restaurants and public transportation.

References to service animals date at least as far back as the mid-16th century; the second line of the popular verse alphabet "A was an Archer" is most commonly "B was a Blind-man/Led by a dog". In the 19th-century verse novel Aurora Leigh by Elizabeth Barrett Browning, the title character remarks, "The blind man walks wherever the dog pulls / And so I answered."

The first service animal training schools were established in Germany during World War I to enhance the mobility of returning veterans who were blinded in combat, but interest in service animals outside of Germany did not become widespread until Dorothy Harrison Eustis, an American dog breeder living in Switzerland, wrote a first-hand account about a service animal training school in Potsdam, Germany, that was published in The Saturday Evening Post in 1927. Earlier that same year, U.S. Sen. Thomas D. Schall of Minnesota was paired with a service animal imported from Germany, but the service animal movement did not take hold in America until Nashville resident Morris Frank returned from Switzerland after being trained with one of Eustis's dogs, a female German shepherd named Buddy. Frank and Buddy embarked on a publicity tour to convince Americans of the abilities of service animals and the need to allow people with service animals access to public transportation, hotels, and other areas open to the public. In 1929, Eustis and Frank co-founded The Seeing Eye school in Nashville, Tennessee (relocated in 1931 to New Jersey).

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