Electrohydraulic lithotripsy was applied in 10 patients with biliary stones which were difficult to extract with the use of choledochoscopy and basket. The difficulties encountered included large impacted stones in the Hartmann's pouch, intrahepatic ducts and lower end of common bile-duct, stones situated at the orifice of acutely angulated segmental bile-ducts and stones impacted just behind strictures. With the use of electrohydraulic lithotripsy all the stones were disintegrated and removed. The only complication was transient haemorrhage from ductal injury. It is concluded that electrohydraulic lithotripsy is a useful adjunct to the choledochoscopic removal of biliary stones.