Coloanal anastomosis after resection of the rectum is the ultimate procedure to preserve the patient's sphincter and avoid a permanent colostomy. Carcinoma of the midrectum, and sometimes of the lower third of the rectum, may not require excision of the pelvic floor and anus for cure. A colonal anastomosis was achieved in 38 patients in whom the indications for surgery were carcinoma in 29, recurrent or extensive adenomas in four, radiation proctitis in two, rectal fistula following radical cystectomy in one, secondary low Hartmann reconstruction after a failed attempt in one, and stenosis of a very low colorectal anastomosis in one. Twenty-six patients were men and 12 women, with a mean age of 62. Dukes' staging for carcinoma were A: 9, B: 7, C: 11, and two had a palliative resection. The mean distance from the anus was 6.0 cm. All had a temporary defunctioning colostomy. There were no postoperative deaths and 17 (45 percent) had postoperative complications, major in 7 (18 percent), minor in 10 (26 percent). Mean follow-up is now 40 months (range, 12 to 64 months). Among patients who underwent curative resection, three have had pelvic recurrences. Two of these patients died of widespread distant disease and one underwent abdominoperineal resection and is now free of disease. All others are alive with no evidence of disease. The colostomy was closed in all but six (16 percent). Two (palliative) died within the colostomy and the other four are awaiting closure. Anastomotic stricture was the most common long-term problem, occurring in 16 and requiring more than one dilatation in eight. Six months after closing the colostomy, the mean daily number of bowel movements is 3.8. Twenty-six (87 percent) are continent to solid stools, two are incontinent to solid stools, and 16 have to wear a pad to prevent soiling. All but one prefer their present status to having their colostomy. In selected cases of rectal carcinoma with little or no extramural spread, the authors estimate that resection and colonal anastomosis is a good alternative with acceptable function and a low rate of recurrent disease, which is comparable to complete rectal excision but avoids a permanent colostomy. However, it should not be a substitute for standard abdominoperineal resection for extensive lower rectal carcinoma or for a colorectal anastomosis when the latter is technically feasible.