Pet ID in the form of a microchip, slightly larger than a grain of rice and inserted under the skin at the back of the animal's neck is probably the first and most important step to making sure that your beloved pet can be properly identified and returned to you should he stray,get lost, or worse be stolen and perhaps sold on. The chip has a unique identification number for your dog, and is registered on a central database that can be updated at any time during the animal's life. If you haven't already done this please ask your vet about this simple procedure which causes little or no pain to your pet but could save you both a lot of pain if you were to be separated through misadventure. I once lost my first labrador Jazz for two desperate days and it was only thanks to the chip scanned by the police that she was identified and traced to me, the eternally grateful parent!
If you want a second increasingly popular method of keeping track of your pet, particulary if he has a tendency to stray, then GPS (Global Positioning System) technology could be the answer. This is the same system used in car satellite navigation systems. In the case of dogs, an ordinary looking collar contains the satnav unit into which the dog's'home run' details are inputted. If the dog moves beyond the geographic boundaries programmed into the collar, the owner is allerted by a telephone, text, or email message. The dog can then be traced to wherever he is using the GPS technology.
Two companies you might want to look at for further inforomation if this clever idea appeals to you are: