Endoscopic papillotomy (EPT) has become a popular form of treatment in managing common bile duct stones. But it may fail in difficult cases such as large stones of over 20 mm, confluence stones, and impacted stones. Over the past 5 years, our success rate in clearing the bile duct by conventional endoscopic techniques (mechanical lithotripsy) was about 90 per cent. Recently, we have performed electrohydraulic lithotripsy or laser lithotripsy with peroral cholangioscopy in these difficult cases. Complete clearance of the duct was obtained in all 23 patients who underwent peroral cholangioscopic lithotripsy. No complication occurred. In conclusion, peroral endoscopic treatment of common bile duct stones should be safe and effective.