Abstract: A proximity monitoring system for individually identifying an object or person, and having a central information processor, and a signal receiver, several remote detectors in various locations at a distance from the information processor, each having a first transmitter for communicating with such processor and having a second transmitter and a receiver, and several individual personalized portable identifiers, each identifier having a continuously activated receiver, a signal transmitter which is normally de-activated, a battery pack, and a switch operated by the receiver in response to a signal from a detector, to switch the battery on to activate the transmitter, for emitting a personalized coded identification signal.