Introduction. The results of colectomy ileorectal anastomosis (IRA) in patients diagnosed by physiologic testing as having slow transit constipation (STC) have been reported (Nyam DCNK, et al. Dis Colon Rectum 1997; 40:273-279). The durability of functional results and long-term quality of life (QoL) in these patients, however, has not been established. Methods. Between 1987 and 2002, 3670 patients were evaluated for constipation at our institution of which 112 (3%) patients fulfilled the criteria for STC and underwent an IRA. Patients were followed through a prospective database and functional outcomes were assessed annually by standardized questionnaires. After a median follow-up of eleven years, 104 eligible patients were mailed validated questionnaire to assess QoL and functional outcomes (Knowles-Eccersley-Scott Symptom (KESS) score, the Irritable Bowel Syndrome Quality of Life (IBS-QOL) and the SF-12 health survey questionnaires. Results. 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. Social activity, household work, sexual life, and family relationships were reported to have improved or were not affected as a result of surgery by 73%, 86%, 82% and 86% of the patients respectively. At 11 years (median) 59, of the 104 eligible (57%) patients responded to the validated QoL and functional outcome questionnaires. Functional outcomes measured by annual standardized questionnaire did not differ significantly between responders and non-responders. All 59 patients reported their constipation to be better since IRA, 83% did not require any constipating or anti-diarrheal medication and 85% reported being satisfied with their bowel function. The KESS score of patients undergoing IRA for STC (median 6, range 0-35) was less than reported scores of patients with STC not operated upon (median 21, range 11-35, P<0.001)(Knowles CH, et al. Dis. Colon Rectum 2000; 43:1419-1426) suggesting symptomatic improvement after operation. Mean IBS-QOL scores were similar to reported scores of patients undergoing IRA for other benign conditions (80 vs. 84, SD20, P=0.7) (You YN, et al. Colorectal Dis. 2005; 7:S1). Mean SF-12 physical and mental summary scores were similar to reported SF-12 scores of the normal population (49.5 vs. 50, P=0.70, 48.7 vs. 50, P=0.42). Conclusion. Ileorectal anastomosis in highly selected patients with slow transit constipation results in durable symptomatic relief and a long-term quality of life indistinguishable from the general population.