This paper summarizes the results of an effort to identify and rank vehicle collision scenarios in order to create a "collision typology" that could aid in the assessment of the potential benefit of accident avoidance technologies. Data from four computerized accident files were used to construct an 18-level collision configuration variable. This variable includes the number of vehicles involved, their relative orientation, intent to turn, relation to intersection, and traffic control at the intersection. Distributions of the collision configuration variable were generated for several factors of interest using 1989 Michigan data. Five of the most prevalent collision types were selected for more detailed review based on the original police accident reports. The case studies lent additional insight into the circumstances of different accident types. Among other findings, the review suggested that in collisions at nonsignalized intersections, older drivers often stopped and then pulled out into oncoming traffic, while younger drivers more often failed to stop at all.