"In this paper we put together a list of the basic instincts that drive and contain travelers' behavior, showing how they mesh with technological progress and economic constraints."

Cities around the world are beginning to prioritize people over vehicles by closing major streets to traffic and opening them up to pedestrians, cyclists, public transit.

"While recent policies directed toward multimodal or complete streets have encouraged increased funding for bicycle- and pedestrian oriented projects, many streets are still plagued by unsafe conditions. This is especially true for one-way streets, which studies show often create unsafe crossing conditions. This study evaluates changes to street dynamics after a two-way street conversion in Louisville, Kentucky. We find that traffic flow increased after implementation of two-way flow, but traffic accidents decreased. We also note other ancillary benefits, such as increase in property values and reduced crime. These results provide evidence that conversions can promote mobility, safety, and livability."