This article attempts to study the sexual behaviour of commercial sex workers and risk in reproductive health including sexually transmitted diseases (STDs) and HIV/AIDS. The data was generated from 200 female sex workers in Tirupati, in Chittoor district of the southern Indian state of Andhra Pradesh. For collection of data, an interview schedule was prepared on the basis of focus group discussions. The profile of the female sex workers included social and demographic variables such as religion, caste, education, age, age at marriage, current marital status, age of entry into the profession, and years in this profession. The respondents were mainly underprivileged women belonging to the lower socioeconomic strata. The reasons for their entry into the profession were mainly poverty, related economic burden, dissolution of marriage, desertion by husband, lack of education, and lack of alternate job opportunities. The study revealed that these women lost a major share of their earnings to brokers/pimps and the police and they faced harassment and sexual exploitation. The article advocates intervention programmes that focus on creating awareness about safe sex and condom use, skill training for income-generating activities, and efforts to integrate STD/HIV/AIDS prevention activities with other ongoing activities such as non-formal education, training in economic activities, micro-enterprise, education and care for their children and free legal aid.