Abstract: An intersection monitor for remote monitoring of traffic intersection controllers. A central computer is connected through the public telephone system to intersection monitors, one of which is located at each remote intersection. The remote intersection monitor monitors the operation of the intersection controllers and related equipment and, upon detecting the malfuntions of a preselected priority, report such malfunctions by placing calls through the public telephone system to the central computer. The central computer, by placing a call on the telephone system, also may interrogate each of the remote intersection monitors and transfer operating instructions to each monitor. Vehicle and pedestrian detectors also are monitored by each remote intersection monitor and unusual activity or inactivity of such detectors is reported by the remote intersection monitor to the central computer.