Animal shelters or (dog) pounds are either governmental or private organizations that provide temporary homes for stray or surrendered pet animals, most often dogs and cats, until the animal is reclaimed by the owner, adopted to a new owner, placed with another organization, or euthanized.

Unfortunately, resources are seldom adequate to support a large number of animals, so animals that are not claimed by their owners or that have temperament or health issues that cannot be corrected or treated within the resources of the organization are often euthanized. Shelters that receive a disproportionate number of animals compared to available adopters may also euthanize an animal because of space concerns.

A small number of shelters are "no-kill" shelters, which support their charges for the remainder of their lives. However, as funding is limited, the number of animals that can be taken is low, and some animals may not be accepted because of behavior or health concerns.

Some people consider pet stores a good place to get a new pet, and a shelter a good place to leave the pet when it gets sick or is no longer wanted. Individuals and organizations are attempting to change that point of view by educating owners and potential owners alike about the large number of adoptable animals available from shelters.

Animal control agencies, or nonprofit organizations contracting for animal control duties, also enforce animal-related ordinances. Some animal shelters also provide low-cost spay/neuter surgeries or veterinary care, behavior training or resources, "safe havens" for animals of abused spouses, or other services.

See also Dog adoption.