An animal rescue group or animal rescue organization is dedicated to pet adoption. These groups take unwanted, abandoned, abused, or stray pets and attempt to find suitable homes for them. Many rescue groups are created by and run by volunteers, who take the animals into their homes and care for them — including training, playing, handling medical issues, and solving behavior problems — until a suitable permanent home can be found.

Rescue groups exist for most pet types (rabbit rescue or bird rescue), but are most common for dogs and cats. For animals with many breeds, rescue groups may specialize in specific breeds or groups of breeds. For example, there might be local Labrador Retriever rescue groups, hunting dog rescue groups, large-dog rescue groups, as well as general dog rescue groups.

Some rescue organizations specialize in a geographic location such as Corridor Rescue Inc. which focuses on an area called The Corridor of Cruelty.

Widely recognized as an umbrella organization for animal rescue groups, Petfinder.org is an online, searchable database of more than 13,000 shelters and adoption agencies across the United States, Canada and Mexico. The American Kennel Club maintains a list of contacts, primarily within breed clubs, with information on breed rescue groups for purebred dogs in the United States.

Animal shelters often work closely with rescue groups, because shelters that have difficulty placing otherwise healthy and pet-worthy animals would usually rather have the animal placed in a home than euthanized; while shelters might run out of room, rescue groups can often find volunteers with space in their homes for temporary placement. Some organizations (such as Young at Heart Pet Rescue, www.yahpetrescue.org and Old Dog Haven) work with older animals whose age would likely cause them to be euthanized in county pounds. Each year, approximately 3-4 million cats and dogs are euthanized in shelters due to overcrowding and a shortage of foster homes.^[1]

In the United Kingdom, both shelter and rescue organisations are described using the blanket term rescue, whether they have their own premises, buy in accommodation from commercial kennels, or operate a network of foster homes, where volunteers keep the animals in their homes until adoption.

Kennels that have a council contract to take in stray dogs are usually referred to as dog pounds. Some dog pounds also carry out rescue and rehoming work and are effectively rescue groups that operate a pound service. Some rescue groups work with pounds to move dogs to rescues. By law, a dog handed in as a stray to a UK pound must be held for seven days before it can be rehomed or euthanized.