The records of 27 patients with colonic ischemia were reviewed. Twelve patients had typical reversible or transient ischemic colitis. Thirteen patients had an ischemic stricture or gangrene of the colon that required operation. Two of the patients had asymptomatic strictures of the splenic flexure and were under observation. The sigmoid colon was the most frequent area of symptomatic stricture formation. Any patient with ischemic colitis, especially that involving the sigmoid colon, should be observed closely for the development of a stricture. Surgical intervention is indicated only after colonoscopy and careful evaluation of symptoms and risk factors.