This paper describes the efforts of one group to improve the biomechanical fidelity of ATD headforms used in automotive crash testing. On the basis of recent cadaver head impact studies and on the literature dealing with facial bone tolerances, several refinements have been made to the Hybrid III head-form. These include a slight modification of effective skull stiffness, the addition of a frangible faceform sub-assembly and the introduction of a compliant mandible. The purpose of these modifications is to improve both the response characteristics to impact as well as to provide a direct means to monitor for facial bone injury.