On the basis of extensive representative traffic accident material (car-to-car and single car accidents) the focal points of real-life accidents were ascertained. The different accident configurations were classified into collision types, and the order of importance was determined according to the frequency of occurrence and the injuries which resulted- In the light of the distribution function of vehicle mass and collision speed, boundary and reference values of a “substitute accident system” were ascertained from real-life accidents. Extensive and detailed studies of accident and car parameters were necessary to provide realistic conditions for the crash tests. The dummy loading values measured in the crash test or calculated by means of a simulation model were compared with real-life injuries in the appropriate mass and speed class. With the help of this correlation, it was possible, by attaching a monetary value to the resultant injuries, to estimate the costs of optimized car structures.