An animal containment system includes a receiver unit carried by the animal.
The
receiver unit includes a GPS receiver for receiving satellite data; a memory for
storing a plurality of waypoints defining a boundary, a stimulation circuit; and
a processor coupled with the GPS receiver and the stimulation circuit. The processor
activates the stimulation circuit at a distance from the boundary when the animal
is within the boundary, dependent upon animal positional variables, and deactivates
the stimulation circuit when the animal is outside the boundary.
