The transportation sector accounts for nearly one third of the US greenhouse gas (GHG) emissions (Green and Shafer, 2003), and until recently, its emissions have kept on increasing. Transportation is also producing a large percentage of local pollutants such as PM, NO2, or CO. Much discussed solutions to address this problem include raising efficiency standards, blending low-carbon fuels with gasoline, or changing land-use patterns through urban design and planning. Another possibility, which has not attracted much attention so far, is to rely on new technologies such as adaptive cruise control (ACC) and inter-vehicle communications (IVC) to improve traffic flow and vehicle fuel economy while reducing the emissions of various pollutants. The purpose of this project is to address this knowledge gap. Using micro-simulation, we will investigate the impact on highway capacity and vehicle emissions when a subset of vehicles are equipped with ACC and IVC technologies, with an application to a section of the I-80. We will then develop driving strategies to maximize energy efficiency of vehicles equipped with IVC and ACC. Quantifying the environmental benefits of these new technologies is important to understand if new technologies like ACC and IVC could contribute significantly to greening transportation.