Perhaps no condition associated with chronic cholestasis is less understood than vanishing bile duct syndrome, a term that refers loosely to the group of acquired disorders associated with progressive destruction and disappearance of the intrahepatic bile ducts and, ultimately, cholestasis. Although the array of insults resulting in poor bile flow is vast, most adult patients who have chronic cholestasis have either primary biliary cirrhosis (or primary sclerosing cholangitis; in some cases, however, a cause cannot be identified. This article reviews the multiple causes, postulated pathophysiology, clinical features, and treatment options for this syndrome.