Liver biopsy specimens previously taken from 16 haemophilic patients with chronic non-A, non-B hepatitis were reviewed. The degree of fibrosis correlated with serum procollagen III peptide (sPIIIP) concentrations, measured both at the time of biopsy and 4.25 years later. Two patients with extremely high sPIIIP concentrations had collateral veins on computed tomography, suggesting portal hypertension. Twenty eight of 47 patients (60%) had splenomegaly on computed tomography, and of 28 patients in whom intravenous contrast medium was used, seven (25%) had collateral oesophageal veins. Serum procollagen III peptide estimations and computed tomography, both non-invasive investigations, indicated that hepatic fibrosis and portal hypertension had developed in a proportion of haemophilic patients with non-A, non-B hepatitis. Infection with the human immunodeficiency virus (HIV) may modify the course of this presumably cytopathic virus infection of the liver.