I bought one of those Garmin dog-tracking units for Jack. It has a sending collar, which he wears, and a handheld GPS unit for me to keep track of him. There are two screens on the GPS related to the dogs programmed into the unit: one shows his compass bearing, distance, and attitude (running, sitting, on point, treeing, etc.); the other shows a map with his position and movement indicated. I've programmed the local landmarks into the map, like cedars, old shop, barn, salt house, storm shelter, autogate, and the corner limits of the compound. It gives him so much more outside, active time than I could give him if I had to go along with him. We've been doing this for a couple of months now and so far he has been very good about limits. Just the other day he did fourteen miles and was never more than seventy yards from the house. The exercise is doing him a lot of good, as can be seen.