This paper provides the status of NHTSA sponsored research on vehicle-to-vehicle and vehicle-to-roadside communications as a means of improving crash prevention performance. A description of Dedicated Short Range Communications (DSRC), the leading wireless technology for vehicle-to-vehicle and vehicle-toroadside communications is presented. Next a discussion of standards development, including the actions of the Federal Communications Commission (FCC) to allocate spectrum, the American Society of Testing and Materials (ASTM) and Institute of Electrical and Electronic Engineers (IEEE) to develop standards, and the Society of Automotive Engineers (SAE) common vehicle-to-vehicle safety message set efforts, are given. Potential vehicle safety applications including intersection crash warning and emergency electronic brake lights are discussed. Discussed next are crash prevention benefits. Finally, message security is covered.