On July 4, 1982 the Space Shuttle Columbia landed at Edwards Air Force Base, California, thus successfully completing the fourth and last in a series of Orbital Flight Tests (OFT) of the Space Transportation System (STS). The primary goal of medical operation support for the OFT was to assure the health and well-being of flight personnel during all phases of the mission. To this end, the crew health status was evaluated preflight, inflight and postflight. Biomedical flight test requirements were completed in the following areas: physiological adaptation to microgravity, cabin acoustical noise, cabin atmospheric evaluation, radiation dosimetry, crew exercise equipment evaluation and a cardiovascular deconditioning countermeasure assessment.