This study was conducted to better understand the psychological and roadway correlates of aggressive driving. The study had two phases: In Phase One, survey data was used to investigate the relationship between personality, emotional, and behavioral variables and self-reported driving behavior-710 people were surveyed. In Phase Two, 67 participants (35 classified as high hostile-those with the most extreme high hostility survey scores-and 32 classified as low hostile-those with the most extreme low hostility survey scores) drove for 19-miles on a simulated four-lane freeway. The data yielded a number of interesting findings; in particular, there were significant differences in driving behavior between drivers characterized as high hostile and those characterized as low hostile. For example, when drivers in the high hostility group were blocked by other vehicles, they responded by driving much closer to the blocking vehicles than drivers in the low hostility group. This risky driving behavior, found in a driving simulator, validates the self reports given by the high hostile drivers in the surveys. This finding is likely to be of value for public safety organizations whose mission is to educate the public about potentially dangerous and risky behavior. It is not likely that all those who are classified as high in hostility will engage in aggressive driving behavior. Further research may yield additional understanding on this point.