Abstract: An infant security system is disclosed which includes a transmitting device that generates at least two uniquely coded signals and is disposed around the leg or ankle of infants in a hospital maternity ward, children's ward or the like. An activated magnetic strip is also attached to the transmitting device. An associated receiver is placed, for example, on the cart containing the infants' crib or bassinet which will typically be close enough to the infant so that it is well enough within the range of the transmitter. Every few seconds the RF transmitter transmits a coded RF pulse. If an infant with an attached RF transmitter is removed by some predetermined minimum distance from its associated RF receiver or if the RF transmitter becomes inoperative or is shielded, then the RF receiver will not receive the transmitted coded signal which will trigger an alarm.