Forty-nine patients with chronic ulcerative colitis refractory to medical therapy and four with multiple polyposis have undergone total colectomy, mucosal protectomy, and endorectal ileal pull-through with ileoanal anastomosis at the UCLA Medical Center during the past 12 years (mean age, 19.4 years). Thirty-eight patients underwent second-stage closure of the ileostomy with construction of a side-to-side isoperistaltic ileal reservoir (mean, 6 months) after the ileal pullthrough operation. The anastomosis extended over a 20-30 cm distance and the lower end was placed within 6-8 cm of the ileonanal anastomosis. Transient reservoir inflammation, which occurred in half of the patients, was reduced by the use of oral metranidazole and was rarely found 6 months after operation. No patients died during the early or late post-operative periods. Cuff abscess in two patients and obstruction of the ileal reservoir outlet have required takedown of the reservoir (two patients) or temporary ileostomy (three patients). Of the 38 patients who have undergone lateral ileal reservoir construction, 33 have achieved a good to excellent result with complete continence and an average of five stools per 24 hours after 6 months. At least 12 patients now participate in competitive athletics; normal sexual activity has been achieved in all but one patient. Seven patients await construction of the reservoir. Although a technically difficult operation, the long-term results (mean, 19.4 months) indicate that the pullthrough operation is a good alternative to standard proctocolectomy.