The experience with 59 patients affected by diverticular disease who underwent surgery after failure of medical treatment, is reported. 40 patients showed one or more postoperative complications, 19 none. The operations performed were: in 46 cases one-stage resection with anastomosis, Hartmann's operation in 8 and other procedures in 5. Six patients died: 3 after Harmann's operation, 2 after colostomy and one after anastomosis. The mean stay in bed for complicated cases was 24 days after anastomosis and 36 after Hartmann's operation. Therefore anastomosis is preferred in all cases including those with stenosis, fistula or abscess provided that peritonitis is not present. The anastomosis is performed away from the site of abdominal sepsis. In cases with peritonitis the selected surgical procedure is usually Hartmann's operation.