The vaccination campaign against hepatitis B for 12-year-old subjects in Italy was evaluated in 136 health districts (USL); 55 in the north, 69 in the centre, and 12 in the south, respectively. Out of the 113,230 eligible subjects born in 1981, 105, 989, (93.6%) completed the three dose series during the period 1993-1994. However, wide geographical differences are observed: the acceptance rate was as high as 97.9% (range 89.7-100.0) and 96.6% (range 76.0-100.0) in the north and in the centre, respectively; but only 65.1% in the south (range 26.8-100.0). Subjects were recruited in the north and in the centre mostly from the list of residents, while in the south more likely only from the list of people attending school. The school attendance in the south, not as good as in the other Italian areas, particularly among people belonging to a subgroup of the population economically disadvantaged, appears to be a strong determinant of the different vaccine coverage observed. Active efforts from health services in southern areas are necessary to reach subgroups of population who escape hepatitis B vaccination and who are also at high risk of HBV infection.