Twelve years of experience with intraoperative and postoperative biliary endoscopy-choledochoscopy is discussed, with special attention given to the developments in equipment and instrumentation technique and results achieved. The outcome of a prospective comparative study evaluating intraoperative diagnostic procedures in biliary surgery as cholangiography and intraoperative ultrasonography is discussed briefly. Finally, the preliminary experience with intraoperative ultrasonography during laparoscopic cholecystectomy is presented.