A series of 21 experimental car-to-car collisions were produced. The accelerations on the thorax and the pelvis of the dummy exposed to the impact were analyzed and related to the parameters linked to the vehicles. Two lateral collisions of a rigid, mobile barrier with a car were produced and compared to the car-to-car collisions. The parameters of the relative stiffness and of the mass of impacting vehicles and impacted vehicles are examined. The protective measures were developed for the impacted vehicle and tested in different configurations.