Conventional health services often present barriers to sex workers seeking health care resulting in untreated sexually transmitted infections (STI) and increased risk of HIV infection. A brothel-based clinic was established to provide STI treatment for sex workers who worked in the inner city suburb of Hillbrow, South Africa. Qualitative research demonstrated that the clinic was acceptable to women in terms of service quality, accessibility, and efficacy, and positively influenced health-seeking behaviours, health awareness, and condom use. The intervention also transformed the image of the hotels from sites of 'dirt and disease' into 'healthy brothels'. The paper concludes that clinical services offered on site are a viable alternative to the provision of conventional clinical services.