Reporting of hepatitis B is not compulsory in France, but it is estimated that 8500-9000 acute cases and 100,000 hepatitis B infections occur every year. Seroprevalence studies have been carried out in selected populations. Every blood donation is screened for HBsAg, alanine aminotransferase elevation and anti-HBc antibody. Prevalence of HBsAg has declined from 13.9 positive donations in 1986 per 10,000 to 5.3 in 1991. In pregnant women, overall seroprevalence is estimated at 0.8-1%, which represents more than 5000 children born each year to carrier mothers. Screening of HBsAg for all women when six months pregnant is now compulsory. Heterosexual patients at STD clinics were shown to have a very high risk of being infected with hepatitis B virus, with a chronic carrier rate of 4-5%. In hospital employees before the introduction of vaccination, the overall incidence of hepatitis B was 100-300 acute cases per 100,000 employees per year. Risk varied according to exposure to blood; the highest incidence was found in nurses in dialysis wards. Vaccination against hepatitis B is now compulsory for all hospital and laboratory workers and medical and paramedical students. In preventive medicine consultants, routine medical check-up showed an overall HBV prevalence of 2.2% and a carrier rate of 0.3% in men and 0.1% in women. Immunization of all newborns and adolescents has recently been adopted in France, vaccination at school of adolescents aged 10-11 years being the main target.