Traffic congestion and motor vehicle crashes are widespread problems, especially in urban areas. Roundabouts, used in place of stop signs and traffic signals, are a type of circular intersection that can significantly improve traffic flow and safety. Where roundabouts have been installed, motor vehicle crashes have declined by about 40 percent, and those involving injuries have been reduced by about 80 percent. Crash reductions are accompanied by significant improvements in traffic flow, thus reducing vehicle delays, fuel consumption, and air pollution.
