Twenty-four colon interpositions were performed in a group of 23 patients comprising both adults and children between 1965 and early 1982. The indications for operation were caustic injury in 13 patients, peptic stricture in 6, congenital atresia or stenosis in 2, and gunshot or foreign body injury in 2. Long colon segments, consisting of isoperistaltic left colon in seven instances, antiperistaltic left colon in four, and right colon in five, were utilized for 16 procedures in 15 patients. Short segments of left colon were used in 8 patients, isoperistaltic in 6 and antiperistaltic in 2. There were no operative deaths. Ischemic complications necessitated removal of the transplant and replacement with another segment in 1 patient and revision or drainage procedures in 2 others. Strictures of the esophagocolic anastomosis occurred in 6 patients. Five of these strictures occurred among the 13 patients with caustic injury and appeared to be due to unrecognized caustic damage in the esophageal segment used for the anastomosis. Three patients died of unrelated causes eight months to 4 1/2 years after operation, and 3 others were lost to follow-up. Seventeen patients were available for current follow-up 1 to 16 years after operation, including 7 who were followed more than 7 years. When the swallowing ability of these 17 patients was assessed using rigorous criteria, 9 were found to have an excellent to good result; 5, a good to fair result; and 3, a poor result. No patient showed late deterioration of function. We conclude that interposed colon is the ideal esophageal substitute for the patient with benign disease.