A dog licence is required in some jurisdictions to be the keeper of a dog. Usually a dog-licence identifying number is issued to the owner, along with a dog tag bearing the identifier and a contact number for the registering organization. If a stray pet is found with the tag, a rescuer can call the registering organization to get current contact information for the dog's owner.

Licensing a dog might require additional actions on the owner's part, such as ensuring that the dog has a current rabies vaccination. In many jurisdictions a fee, which is usually small, must be paid. Licences typically must be renewed annually or after some small number of years.