The basic goal of medical investigations during and after the 366-day mission was to accumulate data about physiological responses to such a long exposure to microgravity. In flight, cardiovascular and other systems were examined in detail and the efficacy of countermeasures used was assessed. After flight, physiological systems were also followed very carefully. According to the preliminary data, the medical results obtained during and after flight give evidence that man can well adapt to a year-long space flight, maintaining good health and adequate work capacity. The readaptation process was very similar to that observed after shorter flights (6-II months). As compared to former flights, no new or qualitatively different changes in the vital systems of the body were seen. The observations indicate that the duration of manned space missions can be further increased.