Service dogs or assistance dogs are working dogs that have been trained to assist people with disabilities. A true service dog is trained to behave well in all types of situations, so the dog can accompany the handler anywhere.
Animal-assisted therapy involves the use of trained, certified animals as part of a medical patient's therapeutic plan. These therapy dogs offer emotional support to sick or injured people, often visiting hospitals and nursing homes.
Police dogs, often called K-9s, are trained specifically to assist police and other law-enforcement personnel in the line of duty. Police dogs protect their handlers. They can chase down and hold criminal suspects who try to run from police.
Similar to police dogs, military working dogs assist members of the military with their operations. These dogs may be used as detectors, trackers, sentries, and scouts. And they can take part in search and rescue.
Detection dogs have exceptional senses of smell and are highly motivated by positive reinforcement. A detection dog is trained to sniff out a particular substance or group of substances.
Search-and-rescue dogs have great agility and exceptional senses of smell and hearing. These highly trained animals serve in many different fields, including tracking, specialized search, avalanche rescue, and cadaver location.
Herding dogs work with various types of livestock, such as sheep and cattle. A herding dog is basically born for the job, meaning the dog is a specific breed and part of a herding breed group. However, not all herding breeds are naturally expert herders.
Guard dogs are considered protection dogs and can be used to protect territory or an owner. These dogs are highly trainable, intelligent, and strong. Guard dogs should be very loyal and are often used by the military or police.
Livestock dogs are used to guard farm animals, particularly sheep. Because these smaller animals can be vulnerable to predators (coyotes, wolves, mountain lions, and more), a livestock dog can be necessary in addition to fencing.