The study done by the U.S. National Highway Traffic Safety Administration (NHTSA) shows that developing automotive collision warning and avoidance systems will be very effective for reducing fatalities, injuries and associated costs. In order to develop an automotive collision warning and avoidance system, it will be necessary that the vehicles should be able to exchange (in real time) their dynamic information such as speed, acceleration, direction, relative position, etc. The only way to exchange the vehicles' dynamic information will be through wireless communications. The communication links among vehicles must be secured. Otherwise, hackers may inject some misleading data into the inter-vehicle messages to make the vehicle systems malfunction. In this paper, we have presented a technique for exchanging vehicles' dynamic information in a secure mode. We also investigated the feasibility of implementing secure inter-vehicle communication links using today's technology. Our study shows that current technology will allow us to build such a system.