The authors report on three cases of cystic duct syndrome, a fairly uncommon complication of cholelithiasis, consisting in migration of a large gallstone from the gallbladder to the common bile duct, resulting in the formation of a common cavity between cystic, hepatic and common bile ducts. They review the pathogenesis of this entity, as well as the diagnostic modalities best suited to a precise diagnosis. They stress that surgical therapy must be chosen on a case by case basis, trying to restore a functional extrahepatic biliary tree.