In order to determine the cellular distribution of androgen receptors (AR) in normal liver and to examine whether phenotypic changes occur in a variety of non-neoplastic liver diseases, cryostat sections of explanted livers removed from 52 consecutive patients undergoing orthotopic transplantation were immunostained using an anti-androgen receptor monoclonal antibody. In histologically normal liver, AR was immunolocalised to the nuclei of hepatocytes. The proportion of positive hepatocytes varied from about 50% to greater than 90%. Staining, of variable intensity, was restricted to parenchymal cells with no evidence of zonal heterogeneity with respect to labelling intensity. In tissue from patients with biliary cirrhoses and in some cases of alcoholic cirrhosis, labelling for AR was observed in areas of ductular metaplasia but not in areas of "typical" ductular reaction (ductular proliferation). Otherwise, no consistent abnormalities in immunolabelling were seen in any of the diseased livers.