The aim of this study was to assess the results of ileal "J" pouch-anal anastomosis in ulcerative colitis. One hundred and fifty six patients operated on between 1983 and 1991 for ulcerative colitis were followed-up prospectively since the surgical procedure with a mean of 29 +/- 16 months (range: 6 to 92 months). There was no postoperative death. Forty-four patients (28%) presented 48 post-operative complications and 14 (9%) were reoperated. Twenty-five patients (16%) were reoperated because of a late complication. Three pouches had to be removed for untreatable fistulas which appeared to be related to a Crohn's disease in 2 cases; the reestablishment of a diverting loop ileostomy was mandatory in 2 further patients for anoperineal sepsis. The mean stool frequency at 1 year was 4.5 +/- 1.9; 40% of patients did not have nocturnal stooling. Daytime and nighttime continence were normal in 90.7% and 77.5% of cases respectively, 87% of patients considered their social life improved by the surgical cure of the disease. The results observed 5 years after the surgical procedure in 37 patients were similar to those observed at 1 year. Twenty-five patients (16%) presented one or several episodes of pouchitis, including 5 cases of chronic pouchitis. It is concluded that the treatment of ulcrerative colitis, ileal "J" pouch-anal anastomosis, is a safe and effective procedure which provides good functional results.