In this prospective study we examined the oral electrolyte-overload method of bowel preparation for patients who were to undergo radical cystectomy and ileal conduit urinary diversion. We found it to be a safe and effective mechanical bowel preparation that can be used by outpatients. It was well tolerated and resulted in adequate bowel cleansing and a low incidence of postoperative wound infections and pyelonephritis. A major advantage of this method is that it reduced the period of preoperative hospitalization.