A process is disclosed to visually capture a person doing a set of steps for an exercise, and then to compare that person during exercise to those steps, measuring the results. Each exercise is tailored to the individual patient, rather than to an “ideal” or “generic” standard. This flexibility allows a physical therapist to optimize treatment for patients progressively, and/or to accommodate multiple physical problems in one patient. This invention can be used as a medical software product under the guidance of a physical therapist for rehabilitation exercises. It may alternatively be used as a fitness or sports training device under the guidance of a trainer or coach. By providing visual data and tracking results, it enhances communication between the physical therapist and the patient (or trainer and athlete), and optionally, the physician.