The focus of road safety in the past has been on reducing the road toll. This resulted in the introduction of legislation making the wearing of seat belts compulsory in Victoria in 1970. This was a world leading approach that has been of great benefit to the Australian community. More recently, it is being recognised that serious injury, particularly long term and irrecoverable injury to the head and neck are a major concern and cost for the individual and the community. Detailed crash analysis in Australia has identified the wide range and frequency of crash types and severities that occur on Australian roads. Varying occupant protection needs have also been identified, in terms of age, sex, size and seating position. An optimising technique has been developed and applied to the design of the restraint system of a new model Holden Commodore passenger vehicle. Various seat belt retention and webbing characteristics, airbag and inflator characteristics, seat stiffness and anti-submarining structures have been considered during the optimising process. A Societal Harm measure of the cost of injury was used to evaluate the effectiveness of the restraint system in providing protection to the community in the range of real-world crashes which occur. This technique is proposed as a more appropriate approach to restraint system design than designing for government regulations or consumer information tests.