Most towns and cities in the United States require dog owners to license their dogs annually. For the town, these fees often defray costs of municipal animal control officers. For the dog owner, the tags that are given out with licenses can be a valuable way to find a lost pet. Although more pet owners are choosing to have their pets microchipped, simple tags are still the first line of defense should a pet become lost. If you find a lost dog with a tag, there are a few simple steps to tracking its owner.