Donald E. Struble holds BS, MS, and PhD degrees from California Polytechnic State University, Stanford University, and Georgia Institute of Technology, respectively, all in engineering with an emphasis on structural mechanics. Dr Struble served as an Assistant Professor of Aeronautical Engineering at Cal Poly–San Luis Obispo, Manager of the Research Safety Vehicle program and Senior Vice President of Engineering and Research at Minicars, Inc. in Goleta California, President of Dynamic Science, Senior Associate at Cromack Engineering Associates, and Senior Engineer at Collision Safety Engineering in Phoenix, Arizona. Dr Struble has worked in automotive crashworthiness since 1972 and in accident reconstruction since 1983. He is coholder of a patent on side impact air bags and was the editor of Advances in Side Airbag Systems, published by SAE International in 2005. He is a member of SAE, AAAM, and Sigma Xi, the Scientific Research Society. Formerly, he was the President of Struble–Welsh Engineering in San Luis Obispo, California, from which he is now retired. John D. Struble holds BS and MS degrees in Mechanical Engineering from the University of Arizona and the Georgia Institute of Technology, respectively. He specializes in automotive and heavy truck accident investigation and reconstruction, and he also has expertise in vehicle structural performance, restraint system analysis, and rollover initiation. Within the area of accident reconstruction, Struble is proficient in momentum, crush energy, and simulation analyses in a wide variety of crash modes. He is also proficient in the extraction of electronic data from accident-involved vehicles and the incorporation of that information into accident reconstruction analyses. Struble served as a Safety Standards Engineer for the National Highway Traffic Safety Administration and Senior Engineer at Struble-Welsh Engineering prior to joining Exponent, Inc., where he is a Principal in the Vehicle Engineering Practice.