The epidemiology of pertussis in Italy is described by using data from the statutory notification system and from seroepidemiology studies. Starting from the 1990s, the incidence of pertussis in Italy has shown a sharp decline and is now at the lowest level ever reached. During this time period vaccination coverage has increased from 88% in 1998 to 95% in 2003. In 1996-97, the prevalence of subjects with levels of IgG antibodies against PT greater than 2EU/ml was 77.6%. The increase in vaccination coverage will probably change the pattern of disease transmission and increase the number of susceptible adults, unless administration of booster doses to adolescents and adults is considered.