We assessed the outcome of stapled ileal J-pouch-anal anastomosis with intersphincteric resection of the anal transition zone in 83 consecutive patients with ulcerative colitis (n = 71) or familial adenomatous polyposis (n = 12). There was no postoperative mortality. Two patients (2.4%) required permanent ileostomy for manifestation of unsuspected Crohn's disease. Major postoperative complications consisted of pelvic sepsis, anastomotic leakage, and pancreatitis with 3.6% each. Both, frequency of bowel movements and degree of continence improved with time. Two years after takedown of the diverting ileostomy 45 patients with ulcerative colitis and 12 with familial adenomatous polyposis were assessed with a frequency of bowel movements of 5.6 +/- 2 and 3.2 +/- 1 per 24 h, respectively (P < 0.05). At this time none of them had major daytime or nighttime incontinence. Minor incontinence was reported by 9% and 14% of the patients with ulcerative colitis during day-time and night-time, respectively. The patients with familial adenomatous polyposis demonstrated better results, without day-time seepage and intermittent nocturnal seepage in only 9%. It is concluded that direct ileal J-pouch-anal anastomosis is a safe procedure with excellent functional results for patients with ulcerative colitis and familial adenomatous polyposis.