Abstract: Occupancy is monitored at a plurality of locations, such as stores, seats or chairs, hotel beds or rooms, doorway passages, service establishments, or the like, and a record is provided of the time of occupancy. The system has respective occupancy-controlled switches in electric circuits providing occupancy signals at the respective locations. These signals are fed via a transmitting circuit, which suitably selects the recorder channels, to a multi-trace recorder, and in conjunction with a clock, provides a timed record of occupancy on the respective recorder traces associated with the monitored locations. The data may be printed on a moving paper recorder strip or may be in the form of magnetic recordings on the magnetic tape of a tape recorder. Timed recordings of fault disturbances may be similarly obtained.