Colostomy is the traditional treatment for acute obstruction of the sigmoid colon. This entails two or three surgical procedures in a high-risk group of patients. Presented is a nonsurgical approach used in three patients with acute colonic obstruction. Decompression of the bowel was achieved with a tube introduced proximal to the obstruction with the aid of a flexible sigmoidoscope. In a fourth patient, in whom the obstruction was next to the splenic flecture, the procedure failed. In all instances where decompression was successful, a one-stage procedure--primary resection and anastomosis--was performed.