This paper describes an on-going investigation of the mechanisms of head injury in motor vehicle accidents. The multidisciplinary approach combines detailed accident investigation with a neuropathological analysis of the injury to the brain. A pedestrian accident model using the MADYMO crash victim simulation package is being developed to be used as an aid in classifying the type and severity of the head impact. Two pedestrian cases are presented with details of the simulation and the neuropathology procedures. The direction of further development of the model is described.