Death and injury on the nation's highways is a public health crisis, especially for youth and members of selected minority groups. The objective of this paper is to review the literature on behavioral and environmental factors that increase risk for traffic morbidity and mortality in populations at high risk. Each of the following is a risky traffic-related behavior: not wearing seat belts, not using child safety seats, not wearing bicycle or motorcycle helmets, driving after drinking, driving while fatigued or distracted, speeding, running red lights, and aggressive driving. Environmental factors that modify risk include urban sprawl, highway design, public policy, racism and economic inequality. High risk groups include youths, males, pickup truck drivers, urban dwellers, the elderly, African Americans, American Indians, and Alaska Natives. A comprehensive approach must be developed for reducing traffic-related risk of death and injury, especially in high risk populations.