This study is designed to assess whether a new technique called facilitated endoscopic retrograde cholangiopancreatography (ERCP) is or is not superior to conventional ERCP for removing stones found in the bile duct at the time of laparoscopic cholecystectomy. ERCP is an endoscopic procedure used to facilitate the radiological examination and subsequent manipulation of the common bile duct (eg. opening it up, which is called sphincterotomy). Both facilitated and conventional ERCP are performed as a separate procedure after the initial gallbladder surgery. This is a comparative study of these two techniques in a randomised clinical trial.