Indonesia in predicted to face a severe AIDS epidemic in the near future. More than 60% of the reported HIV positive cases in Indonesia can be attributed to heterosexual transmission; therefore, by the nature of their work,female commercial sex workers (FCSWs) constitute one of the communities at risk. No meaningful or effective STD/HIV prevention programs for FCSWs can be planned if there is no contextual understanding of these women as persons, the nature and the risk of their job and their relations with their clients and managers. Just as it is incorrect to assume that all women enter prostitution for the same reasons, educational approaches that are modeled on shallow stereotypes will be ineffective. Interweaving qualitative and quantitative methods, this research investigates the FCSWs in an 'official' brothel complex in Jakarta, Indonesia. Results of this study give insight of four typologies of FCSWs observed in Kramat Tunggak. The personal, professional, social and other differences which influenced the woman into full-time sex work and affected their willingnes and ability to engage in healthy and protective behaviors, are presented. Finally, based on those findings a recommendation on how to deliver health messages to the FCSWs is offered.