The results of colectomy and ileorectal anastomosis (IRA) in patients diagnosed by physiologic testing as having slow transit constipation (STC) have been reported. The durability of functional results and long-term quality of life (QoL) in these patients, however, has not been established. Between 1987 and 2002, 3670 patients were evaluated for constipation at our institution; 110 (3%) fulfilled the criteria for STC and underwent an IRA. Patients were prospectively followed and functional outcomes assessed annually by standardized questionnaires. After a median follow-up of 11 years, 104 eligible patients were mailed validated questionnaires to assess functional outcomes and QoL (Knowles-Eccersley-Scott Symptom [KESS] score, the Irritable Bowel Syndrome Quality of Life [IBS-QOL], and the SF-12 health survey). Prospectively assessed functional data was available on 85 of 104 (82%) eligible patients. At last follow-up, improvement of constipation and satisfaction with bowel function was reported by 98% and 85% of patients, respectively. Performance measures including social activity, household work, sexual life, and family relationships were reported to have improved or were not affected as a result of surgery by 75%, 86%, 81%, and 86% of the patients respectively. Fifty-nine patients (57%) responded to the study questionnaires. All 59 patients reported their constipation to be better since IRA, 83% did not require any medication, and 85% reported being satisfied with bowel function. The KESS scores of patients undergoing IRA for STC (median 6, range 0-35) were lower than reported scores of STC patients not operated upon (median 21, range 11-35, P<0.001) indicating symptomatic improvement after surgery. Mean IBS-QOL scores were similar to reported scores of patients undergoing IRA for other conditions [80 (23) versus 84 (16)], P=0.7). Mean SF-12 physical and mental summary scores were similar to reported SF-12 scores of the normal population (49.5 versus 50 and P=0.70, 48.7 versus 50, P=0.42, respectively). Ileorectal anastomosis in appropriately selected patients with slow transit constipation results in durable symptomatic relief and a long-term quality of life indistinguishable from the general population.