A method of closed treatment of ruptures of the Achilles tendon is advocated. This system provides for a period of casting for ten weeks, eight of which are with the foot immobilized in gravity equinus. The use of a long leg cast for the first six weeks is justified to allow relaxation of the gastrocnemius muscle. Clinical evaluation and experience in treating eight patients reveal a consistently good result with a minimum of complications. The inherent risks of anesthesia and surgery are avoided. The postoperative problems associated with surgery on the Achilles tendon are not present.