Eighty-four patients had colectomy with ileostomy and oversewing of the rectum for Crohn's colitis. Seventy-two patients were operated on because of intractable disease, colitis in combination with rectal fistulas, and toxic megacolon. The operative mortality was 6 percent, and neither emergency surgery nor treatment with steroids correlated with operative morbidity. After a median 7.7 years of follow-up, 25 ileorectal anastomoses had been undertaken, 16 of which were successful. Twenty-nine protectomies were performed; the resulting 10-year cumulative risk of proctectomy was 50 percent. While the risk of proctectomy was significantly less among patients with a normal rectum at colectomy compared with patients with proctitis, the initial macroscopic degree of proctitis did not correlate with the risk of subsequent proctectomy. The 5-year cumulative ileal resection rate in 29 patients with a rectum in situ but out of circuit was 29 percent. The possibility of a future ileorectal anastomosis should still be considered in patients with proctocolitis.