At Citywide Animal Clinic, we use Schering Animal Health's HomeAgain Microchip Identification System to identify your pet should he or she become separated from you. A small microchip about the size of a grain of rice is placed under the skin and between the shoulder blades of your dog or cat, in much the same manner as we would vaccinate your pet. Each chip has a unique code that is entered into a national database. At all shelters, a hand-held scanner "swiped" over the back of your pet picks up the number in very much the same way your groceries are scanned. That is all that is needed for the shelter to start their efforts to put you back in touch with your lost pet.