Abstract: The unique advantages of computer-controlled fabrication of a patient-specific orthotic device using an automated fabrication machine capable of following computer instructions to create 3D surface contours and new developments in non-invasive three-dimensional (3D) scanning have made it possible to acquire digital models of freeform surfaces such as the surface anatomy of the human body and to then fabricate such a patient-specific device with high precision. Such a patient-specific device brings significant improvement in patient-specific fit, comfort, and function of medical devices (and, in particular, to orthoses that require a close fit to the wearer's body to act effectively). The combination of these two technologies is ideally suited for the development of patient-specific orthotic devices. A patient specific ankle-foot orthotic device using this technology is disclosed. This exemplary device is used to help stabilize the ankle-foot region, for example, in patients with impaired gait.