OBJECTIVES: Persons engaged in the sex industry are at greater risk of HIV and other sexually transmitted infections than the general population. One major factor is exposure to higher levels of risky sexual activity. Expanding condom use is a critical prevention strategy, but this requires negotiation with those buying sex, which takes place in the context of cultural and economic constraints. Impoverished individuals who fear violence are more likely to forego condoms. METHODS: Here we tested the hypotheses that poverty and fear of violence are two structural drivers of HIV infection risk in the sex industry. Using data from the European Centre for Disease Prevention and Control and the World Bank for 30 countries, we evaluated poverty, measured using the average income per day per person in the bottom 40% of the income distribution, and gender violence, measured using homicide rates in women and the proportion of women exposed to violence in the last 12 months and/or since age 16 years. RESULTS: We found that HIV prevalence among those in the sex industry was higher in countries where there were greater female homicide rates (β = 0.86; P = 0.018) and there was some evidence that self-reported exposure to violence was also associated with higher HIV prevalence (β = 1.37; P = 0.043). Conversely, HIV prevalence was lower in countries where average incomes among the poorest were greater (β = -1.05; P = 0.046). CONCLUSIONS: Our results are consistent with the theory that reducing poverty and exposure to violence may help reduce HIV infection risk among persons engaged in the sex industry.