Abstract: Objective: Prostitutes are at great risk of sexually transmitted infections (STI). The aim of this project is to evaluate the prevalence of STI among prostitutes and the importance and feasibilty of a hepatitis B vaccination programme. Methods: Prostitutes, women and men, were reached at different places, in and around Antwerp, Belgium, in or nearby their workplaces, during their working hours. Outreachers informed and tried to motivate prostitutes to participate in the programme. The prostitutes were screened for HBV, HIV, syphilis, gonorrhoea and chlamydia. Prostitutes were inter­viewed about their practices at risk for STI in their profession. Those neg­ative for HBV were offered hepatitis B vaccines. Results: From September 1999 to December 2000, 120 prostitutes took part in the programme. The prevalence of past hepatitis B infection was 22.5%. 44 persons were working in window prostitution, 38 on the street, and 37 in bars outside the city centre; 3.3% was seropositive for HIV; fourteen per cent was seropositive for syphilis. There is a substan­tial difference in population characteristics between window and street prostitutes and those working in bars. Bar prostitutes are mainly Belgian women. In the other two groups more prostitutes with a foreign nationality are seen. The latter show a higher prevalence for STI seromarkers. By december 2000, 86% (68/79), 87% (54/62) and 72.5% (29/40) individuals had received respectively a first, a second, or a third dose of vaccine. Conclusion: STI screening and hepatitis B vaccination in prostitutes is feasible, on the condition that the necessary manpower can be invested in the programme and that an outreach structure can be created to support this programme. Specific efforts for health education, prevention and cure of STI among prostitutes are necessary.