Background. Despite recognition of their central role and power in decision making around sexual behaviors, very little is known about the social networks of male partners of female sex workers. This dissertation explores how social network norms influence HIV-related behaviors among the male partners of female sex workers in La Romana, Dominican Republic.

Methods. A quantitative socio-behavioral survey, including a personal network component, was carried out with 380 male partners of female sex workers recruited at thirty-six commercial sex establishments. Multiple in-depth interviews each (n=20) were conducted with a sample of eleven male partners of female sex workers recruited at seven different commercial sex establishments.

Results. Manuscript one identified a positive significant association between perceived condom use among male social network contacts (descriptive norm) and consistent condom use (CCU) among male partners. Communication about condoms was also significantly associated with CCU. These associations were only significant among male partners with lower alcohol consumption frequency. While encouragement towards condom use (injunctive norm) was not associated with CCU, Manuscript two found that encouragement and expressing dislike for condoms were significantly associated with perceived condom use among male social network contacts. Finally in Manuscript three, male partners revealed a shared perception that they should “cuidarse”, or be careful, by using condoms with female sex workers. This perceived norm is reinforced through a constant exchange of advice between social network contacts. In response to normative pressures, some male partners also revealed that they lie to their social network contacts about their condom use behavior to avoid social sanction.

Conclusions. Taken together, these results indicate that the normative beliefs and behaviors of social networks may influence condom use among male partners of female sex workers. Specific forms of communication appear to shape the perceptions of these norms. However, normative pressures can also push men to hide their actual behavior, and the effect of alcohol can overcome positive normative influences at the crucial moment of sexual decision making. Further research is needed to inform the development of social network based HIV prevention approaches that build upon male partners' natural social dynamics to promote sustainable change.