In Europe, as hygiene conditions have improved, the incidence rate of hepatitis A has declined over the past few decades. This decline is confirmed in France by seroprevalence surveys among conscripts (from 50% in 1978 to 10% in 1997). This change has led to an increase in the number of susceptible individuals in adulthood, the age at which 70 to 80% of infections are symptomatic and often more severe. Since 1992, a vaccine against HAV, with no notable side effects and a seroconversion rate exceeding 95% after the first dose, provides protection for 10 to 20 years. It is currently recommended for certain at-risk groups. In France, mandatory reporting of acute viral hepatitis was abolished in 1984. Since then, hepatitis A surveillance systems have provided heterogeneous data regarding the information collected and the methods used to gather it. The objective of this article is to identify the hepatitis A surveillance systems that have existed in France since 1984 and to evaluate their ability to measure the annual incidence rate of hepatitis A. (R.A.)