Abstract: A nationwide, web-based pet registration, search and retrieval system. The system is implemented with a host computer (10) that may be accessed by users operating user computers (12) via a communications network (14) such as the Internet. Pet owners may register their pet with the host computer and finders of lost pets may search the host computer in an attempt to locate the owners of lost pets. Preferably, the rabies vaccinated pet wears a single multi-purpose tag which communicates both the pet's rabies vaccination information and information for reuniting the pet with its owner. Rabies vaccination is not a prerequisite, however, and almost any relatively unique identifier will work, including microchip numbers, tattoos, other types of identification tags, etc. The system also allows an owner to license the pet with a participating municipality.