Head injury sustained in accidents remains a leading cause of death and disability, even though considerable advancement has been made with respect to injury prevention. Successful prevention relies on a sound understanding of injury mechanisms and knowledge of the biomechanical responses, as investigated in various experimental studies. The increased use of human body models (HBMs) and computational brain models, respectively, continues to offer new insights. Accordingly, previous research has been critically questioned, new experiments have been conducted and new injury criteria have been proposed.