Crashes involving passenger car drivers in head-on collisions were examined for changes in injury patterns due to increasing seat belt and air bag availability. Annual injury costs and incidence levels (by body region and severity) were estimated for years 1990 through 2005. Over that period, severe injuries and fatalities are anticipated to decrease by 10% and 35%, respectively, despite a predicted 54% rise in the number of head-on crashes. Upper and lower extremity injuries, however, are expected to increase in terms of cost and incidence, while brain and trunk injuries diminish. Moreover, lower extremity injuries are projected to move ahead of trunk and brain injuries to become the most costly injuries by 2001.