A system for reducing the likelihood of collision between a first vehicle and a second vehicle in an intersection. Each of the first and second vehicles includes a device for receiving global positioning system (GPS) signals, generating at least one of a time, position and velocity signal based on the received GPS signals, generating at least one of a time, position and velocity signal based upon the motion of the vehicle, comparing the two signals, generating a corrected vehicle signal, and transmitting the corrected vehicle signal. A traffic flow controller controls traffic flow through the intersection. The traffic flow controller receiving the corrected vehicle signals, calculates from the corrected vehicle signals the likelihood that the positions of the first and second vehicles will coincide in the intersection, and generates a traffic flow control signal adapted to minimize the likelihood of coincidence of the first and second vehicles in the intersection.