Preliminary studies of the seroprevalence of hepatitis C antibody (anti-HCV) in selected New Zealand populations, reveal similarities to other Western countries. High rates occur in haemophiliacs and intravenous drug users with relatively low rates in routine blood donors. Unlike hepatitis B virus infections anti-HCV does not appear to be more prevalent in Maoris and Pacific Islanders living in New Zealand. Chronic liver disease is associated with anti-HCV. The frequency of anti-HCV in homosexuals and persons attending sexual disease clinics is higher than that found in blood donors. Further detailed studies of the frequency of anti-HCV in New Zealand populations are now required to extend the present baseline data.