Of 2,212 patients who underwent radical retropubic prostatectomy for the treatment of prostate cancer, 27 had documented rectal injuries. All but one were detected immediately at the time of surgery and were repaired; a temporary diverting colostomy was established in 6 patients. Follow-up on these patients ranged from nine to one hundred eighty-five months (mean, 68 months). Four patients had fistulas between the rectum and the urinary tract that required additional surgery. Factors that predisposed patients for intraoperative injury to the rectum include a history of previous pelvic radiation therapy, previous rectal surgery, and previous transurethral resection of the prostate (P < 0.01). Higher local tumor stage did not significantly increase the risk of rectal injury at the time of radical retropubic prostatectomy. Preoperative bowel preparation may obviate colostomy; it may still be necessary in high-risk patients with suboptimal local repair.