This study attempted to describe patterns of infection with, and risks for, hepatitis A, B and C viruses in male adolescents by means of a cross-sectional serosurvey among 90 of the Melbourne Juvenile Justice Center's residents aged 15 to 18 years. The residents were vulnerable to exposure to blood-borne viruses from an early age, posing a challenge for health education programs. Although most in the study group knew about clean needles and syringes, the majority shared equipment and knowledge of cleaning techniques was poor. The article suggests that harm-reduction programs need to be non-discriminatory, easy to understand and accessible. Education should use means that will appeal to adolescents in places where they congregate. Such initiatives must be undertaken early. Peer-based education programs currently in place in the juvenile justice setting are well accepted but need ongoing evaluation in terms of preventive efficacy. Figures, table, references