In Korea, the total number of vehicles was 8,470,000 in 1995, but it has increased to 17,033,715 in June 2009. The massive increase of the number of vehicles on the roads have caused serious social and environmental problems. The major underlying problems which we are now suffering from are traffic congestion, traffic accident and air pollution. The motor vehicles are a major source of common air pollutants, including Carbon monoxide (CO), hydrocarbons (HC), volatile organic compounds (VOCs), and oxides of nitrogen (NOx). Many efforts have been made to find approaches which would lead to the solution of transportation problems. The main approaches are constructing road infrastructure, installing Intelligent Transportation Systems(ITS), and providing an efficient traffic operation. Normally, many traffic problems such as traffic accident, congestion and air pollution on roads occure at the intersections and they can be mitigated by changing Traffic Signal Intersection to Roundabout. In this study, various strategies on facilities improvement, operation and policies, have been considered to construct a