For many years, open exploration of the common bile duct has been the treatment of choice for patients with common bile-duct stones. During recent decades endoscopic sphincterotomy has gained wide acceptance as an effective and less invasive alternative. After sphincterotomy, subsequent (laparoscopic) cholecystectomy is warranted in patients with gallbladder stones. This chapter will discuss whether sphincterotomy should be performed prior to, during or after cholecystectomy, and will also address the question of whether single-stage treatment by laparoscopic cholecystectomy and laparoscopic bile-duct exploration is in fact preferable. The rate of recurrent choledocholithiasis after endoscopic biliary sphincterotomy can reach more than 20%. This review focuses on the risk factors--delayed bile-duct clearance and bactobilia--that may lead to recurrent primary bile-duct stone formation. Underlying altered bile composition (relative phospholipid deficiency) should be recognised in a subgroup of patients. Identification of these risk factors may significantly affect treatment policy.