Most researchers studying sex work have focused on the risks of sexually transmitted diseases, predominantly HIV, for sex workers, their clients, and subsequent partners. Violence against these women often goes undocumented and unnoticed. Consequently, few researchers have addressed violence against sex workers, and these few have generated limited evidence about the nature of violence from the sex-worker perspective--especially the street sex worker perspective. In this study, we used qualitative methods to explore characteristics of violence against street sex workers and how violence influences personal and societal health risks. The participants were 28 female street sex workers. The data were collected through in-depth interviews with 23 women, one focus group with 5 women, and observations of these women in their working and social environment. The results revealed that violence against sex workers can be clustered into three categories, threat to their life and health, threat to control of work and financial security, and finally, threat to humanity. Because they are disadvantaged, and engage in illegal employment, theses women were trapped in a circle of threats. To reduce violence, sex work should be decriminalized along with strategies to decrease poverty and social inequality. A special agency needs to be established to protect the rights and safety of sex workers.