This paper summarizes the results of an effort to identify and rank collision scenarios in order to create a "collision typology" which could aid in the assessment of the potential benefit of accident avoidance technologies. An 18-level collision configuration variable was constructed which included the number of vehicles involved, their relative orientation, intent to turn, relation to intersection, and traffic control at the intersection. Distributions of this variable were generated for several factors of interest using data from four computerized files. Five of the most prevalent collision types were selected for more detailed review based on the original police accident reports.