This paper discusses the problem of occupant protection in severe rear-end collisions from the standpoint of high performance seat structures and head restraints. Consideration is given to both fixed head restraints and to deployable head restraints. Two-dimensional computer simulations of occupant kinematics in a variety of rear-end collisions are utilized to provide initial performance criteria for head restraint design configurations. The resulting prototype system underwent a test and development program on an impact sled. The results of the various prototype performances and general criteria for high performance head restraint systems are discussed.