Antibodies to hepatitis C virus (anti-HCV) were determined in an unselected group of 340 patients with chronic renal failure treated with maintenance dialysis. A second generation hepatitis C virus (HCV) enzyme-linked immunosorbent assay (ELISA) was used and confirmation made by a second generation recombinant immunoblot assay (RIBA). Sixteen patients (4.7%) were anti-HCV positive and 8 (2.4%) were anti-HCV indeterminate. All anti-HCV positive and anti-HCV indeterminate patients had received blood transfusions. No statistically significant differences were found between anti-HCV positive and indeterminate patients considering blood transfusions, dialysis and liver disease. The combined group of anti-HCV positive and indeterminate patients had had more blood transfusions (P < 0.005) and had been on dialysis for a longer period (P < 0.01) compared with anti-HCV negative patients. Further, significant correlation with elevation of transaminases and anti-HCV was observed (P < 0.001). Thirty patients (8.8%) had elevated transaminase levels and 13 (43%) of these were anti-HCV positive or indeterminate. In conclusion, HCV infection accounts for a substantial proportion of liver disease in dialysis patients, probably most often transmitted by blood transfusions but other routes of transmission could not be excluded.