The success of air bag systems is clear. Air bag systems are now practical and effective as supplemental restraints for reducing the risk of injury in certain classes of vehicles and in certain collisions, but several key challenges remain. For example, the air bag inflator supply base is still fragile. There are also a number of customer misconceptions resulting from differences between customer beliefs about air bag systems and actual air bag system operation and field performance. Field investigation will continue to be critical to the automotive industry and the research community’s understanding of real-world occupant restraint system performance. Field experience has demonstrated that the combination of safety belts and air bags now provide the best overall risk reduction, but only if safety belts are used, and used properly. Hence, there will continue to be a critical need to promote the proper use of safety belts.