Dudley S. Childress is Professor of Physical Medicine and Rehabilitation at the Northwestern University Medical School in Chicago and Professor of Biomedical Engineering in the McCormick School of Engineering and Applied Science in Evanston, Illinois. He directs the Prosthetics Research Laboratory and the Rehabilitation Engineering Research Center in Prosthetics and Orthotics and serves as Executive Director of the Prosthetics & Orthotics Education Program, all at Northwestern. His current interests include the design and development of artificial hands and arms, human ambulation, and assisted-ambulation mechanisms.