The rate of adoption of new vehicle technologies and related reductions in petroleum use and greenhouse gas emissions rely on how rapidly technology innovations enter the fleet through new vehicle purchases. New technologies often increase vehicle price, which creates a barrier to consumer purchase, but other barriers to adoption are not due to increased purchase prices. For example, plug-in vehicles, dedicated alternative fuel vehicles, and other new technologies face non-cost barriers such as consumer unfamiliarity or requirements for drivers to adjust behavior. This report reviews recent research to help classify these non-cost barriers and determine federal government programs and actions with the greatest potential to overcome them.