Abstract: A system for automatically controlling lighting fixtures, appliances, an alarm, or the like in a room or enclosure has a pair of sensors installed in association with each entryway leading into a room. The sensors are triggered when a person passes through the entryway and send a signal to a logic circuit which is mounted in operative association with the sensors. The logic circuit distinguishes between entry or exit of persons from the room on the basis that in each entryway or door one of the two sensors is triggered first in case of entry, and the other one of the two sensors is triggered first in case of exit. The signals signalling entry are counted and stored in a first counting register separately from the signals signalling exit of persons from the room which are counted in a second counting register. The status of the first counting register storing the number of entries is continuously compared in a comparator circuit to the status of the second counting register storing the number of exits.