Abstract
This chapter addresses the repeated occurrence of traffic congestion that is primarily caused by urban commuters on highways, freeways or other trunk roads at the borders of high density urban areas. It evaluates the merits of increased rail and/or bus investments with the sole goal of reducing automobile traffic. The chapter concludes that, though investments in public transit have merit - improving access to certain areas, guaranteeing mobility to some groups of people, and other benefits - research studies have shown that increasing public transit availability does not result in substantial shifts of automobile traffic to public transit.