Current restraint systems with pretensioner, belt force limiter and airbag are not only designed for a crash test such as FMVSS 208. Automobile manufacturers carry out test configurations over and above these parameters to check the effectiveness of restraint systems, for instansce: NCAP, frontal crash with 40% offset against a deformable barrier, which is a provision of the ECE-R 94 and a binding prescription for all new European vehicles as of October 1998. However it is not possible to cover the entire spectrum of accident configurations found in real-world accident occurrences.In the development of restraint systems with reference to aspects of occupant biomechanics, the possibilities on the testing side for reproducing reality are particularly limited. Aside from the 50%-HYBRID III dummy as occupant of average size and weight, only the two extremes of the occupant - 5% female dummy and 95% male dummy - are used.This paper defines the concept of Adaptability of the restraint system, that is the adaptability of its protection performance to various different possible initial parameters such as type and severity of accident, and the occupancy/car interior/ constellation. The adaptation requirement for the restraint system is determined in an occuparcy/car interior model with simulation for individual crash occupancy combinations in a frontal crash. With the help of selected crash configurations with high adaptation requirements on the restraint system (RS), the potential of such restraint systems with regard to the increase in occupant protection is demonstrated. The question of the value of adaptability should be discussed in comparison to a restraint system which has been alternatively further optimized by primary measures.