Assistance dog

    An assistance dog is a dog trained to aid or assist a person with a disability. Many are trained by a specific organization, while others are trained by their handler (sometimes with the help of a professional trainer).

    There are three general "types" in which an assistance dog may be further classified. Most assistance dogs will be trained for only one of these, though "combination" dogs do exist.

    Guide dogs assist the blind and the visually impaired.

    Hearing dogs, or signal dogs, help the deaf and hard of hearing.

    Service dogs refers to dogs not specifically trained for visual or hearing impairment, but trained to do other work, such as mobility assistance dogs, seizure alert dogs or other medical alert dogs, and psychiatric service dogs. In the United States, the term "service dog" may be used synonymously with "assistance dog," and is occasionally used for other types of working dogs as well.