Abstract: In a theft protection system, particularly for a shop area, several exit passages with individual antenna systems are surveyed by means of a single transmitter for the transmission of electromagnetic interrogation signals and a single receiver for reception of resonance signals generated by unauthorized removal of a good, the antenna system for all the exit passages being connected to the transmitter and the receiver through multiplexers. A central control unit controls the multiplexers so as to actuate the antenna systems in successive time frames, whereby only one antenna system is made operative at a time. With each exit passage is associated an alarm device which is only activated for an alarm release from an alarm-actuating circuit connected to the control unit in case of compliance with at least one positive and one negative alarm criterion.