Abstract: A vehicle detection apparatus using existing traffic preemption technologies to include automatic vehicle location, remote traffic preemption, and central decision support system for transit, congestion and emergency vehicle control. The apparatus includes emitters mounted on emergency or transit vehicles to activate and preempt existing intersection control systems, automatic vehicle location protocol, real time mapping of intersections within the system, and interconnecting communications means for transferring the system output data to the respective control or data receiving center. The preferred embodiment of the present invention uses a wireless modem with embedded software protocol connected to the preemption card installed at a typical traffic intersection controller cabinet. As vehicles approach the intersection, the wireless modem reports the location and preemption information to the control center.