Abstract: A traffic control system for controlling vehicular traffic flow at intersections in which the conventional red, yellow, green three light traffic signal that informs a motorist to stop, prepare to stop, and go is supplemented by an auxiliary signal spaced from the intersection. The auxiliary signal informs a motorist that he will have sufficient time to make a gradual normal stop at the intersection before the red stop light is switched on, provided he has not passed the auxiliary signal when the yellow light of the traffic signal is illuminated. If he has passed the auxiliary signal when the yellow light of the traffic signal is switched on, he will know that he can proceed through the intersection before the red stop light is switched on. The auxiliary signal may be a single or double yellow light operating in synchronism with the yellow light of the traffic signal, or it may be another type of signal, such as a painted zone on the roadway surface.