Since autoimmune processes are probably involved in the early stages of primary biliary cirrhosis (PBC), immunomodulatory drugs have been investigated with the aim of prolonging survival, delaying transplantation, slowing histological progression and relieving symptoms. Corticosteroids, azathioprine, chlorambucil and, more recently, cyclosporin A and methotrexate have all be subjected to clinical investigation. In the latest of these, a European multicentre trial, cyclosporin A has been shown to delay death or transplantation with a reduction in liver related deaths and slowing of the rise of serum bilirubin. The incidence of nephrotoxicity and hypertension are low at the doses used.