Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are the two most common causes of chronic cholestatic liver disease in adults. In PBC, therapy with ursodeoxycholic acid (UDCA) is safe and has been associated with tangible biochemical, histologic, and survival benefits. However, a need for different or adjuvant therapies remains for specific subsets of PBC patients, including those who do not respond to UDCA and those who have advanced histologic disease at presentation. Similarly, beneficial therapies for disease-related symptoms that do not typically respond to UDCA (eg, fatigue and pruritus) are still needed. In contrast to PBC, no medical therapy of proven benefit has been identified for patients with PSC. In PBC and PSC, adequate management of complications of chronic cholestasis is important. For both diseases, liver transplantation is the only curative option. © 2010 Springer Science+Business Media, LLC.