In general, an assistance dog, known as a service dog in the United States, is a dog trained to aid or assist an individual with a disability. Many are trained by an assistance dog organization, or by their handler, often with the help of a professional trainer.
It's important to differentiate between Assistance or Service dogs and Emotional Support Animals. Unlike Assistance or Service dogs, Emotional Support Animals are not protected under the ADA laws or the Disability Act 2010 (UK) and typically have little to no training in comparison to an assistance or service dog.
Terminology
'Assistance dog' is the internationally established term for a dog that provides assistance to a disabled person, and is task-trained to help mitigate the handler's disability. Assistance Dogs International, an international network of assistance dog providers across the globe, notes that there is some variability of terminology in different states, particularly within the United States. They are working to establish consistent global terminology, and note that 'assistance dog' is the term adopted by organizations who train and provide assistance dogs, and the disabled people who partner with assistance dogs.
Distinctive features
For a dog to be considered an assistance dog, they must meet the following criteria:
The dog's partner must be disabled and meet the legal definition of disability in the specific country or region. The dog must be specifically trained to mitigate the partner's disability in some way, e.g. opening doors, detecting high blood sugar or allergens and notifying of such, alerting to a ringing phone, leading those who are visually or mobility impaired. The dog must be trained to a high level not to be a nuisance in public, to be safe with members of the public and well-behaved, as well as being healthy and not posing a hygiene threat. Individual countries and regions will have specific laws and regulations, with these international criteria having broad recognition across the globe.
Training process
Assistance dogs have traditionally been trained by charities and other organizations who then partner a disabled person with a trained dog when the dog has completed its training program at approximately the age of 2. Increasingly, more disabled people are self-training their own assistance dogs, whereby the disabled person selects their own dog (often referred to as a 'prospect') and the dog is trained by the disabled person who also becomes their eventual handler. There is great variability between the length and type of training that any future assistance dog receives; however, all assistance dog candidates will go through certain stages.
Selection
Assistance dog candidates are generally selected with care for appropriate health, temperament and characteristics. Large established organizations such as The Guide Dogs for the Blind select and maintain their own breeding stock to ensure healthy pups with desirable traits. Someone may carefully select prospect puppies from reputable breeders, or they may choose to commence training with a dog who was already part of the family. The reality TV show Rescue Dog to Super Dog featured the process of carefully selecting rescue dogs from shelters to train as assistance dogs.
Socialization
The first period of a puppy prospect's life is normally spent in socialization rather than formal training. Large formal organizations often use puppy foster parents during the pups first year and the pup grows up in a normal family environment surrounded by the sights, sounds and smells of the type of environment they will later work in, learning to be clean and toilet trained, confident and happy. Owner Trainers raise their pups themselves, so the dog lives with the same person who will later be their handler, but will also focus on giving the puppy confidence, play experiences and socialisation in the environments they will later work in.