A man with a visual impairment is using an elliptical trainer.

People who are blind or have a severe visual impairment use guide dogs. The individual must be deemed legally blind in order to qualify and obtain a guide dog. Guide dogs are mobility aides that assist people in navigating through their daily activities. Guide dogs know when to stop for traffic, crosswalks, steps, or curbs. These dogs can be trained to navigate the layout of a facility (such as a fitness center) and will stop when an obstacle (such as a person or object) is blocking the path of their owner.

Hearing dogs can be useful in many ways to a person who is deaf. Hearing dogs can alert their owners when someone is knocking or ringing a doorbell, when the telephone rings, when an alarm is sounding off, or when a specific name is being called. It is the duty of these dogs to get their owner's attention by using physical touch with their nose or paw, and then leading the owner to the cause of the noise or sound.

Service dogs offer the greatest range of abilities, in that they are trained to perform a multitude of physical tasks such as; pulling a wheelchair, retrieving objects like a newspaper, a remote control, or plastic bottle of water from the refrigerator, opening doors, or turning on light switches.

All assistance dogs, regardless of type, must be able to do three things successfully: relieve themselves on command, ignore unattended food (whether on the ground or on a table), and ignore other people when they are working. Section 36.302(c) of the Americans with Disabilities Act requires public accommodations generally to modify policies, practices, and procedures to permit people who are blind or disabled to be accompanied by working dogs anywhere.

Having playtime is just as important as working for assistance dogs. When the dog is not wearing its harness, it is free to play and just be a dog. Because these dogs play such a large role in the lives of their owners, many become a member of the family unit.