Preliminary data from pregnant women in rural Kenya indicate that fear of violence from a male partner is an important reason why some women refuse HIV testing, and that pregnant women who test HIV-positive or refuse testing may be more likely to be victims of violence. In response to these findings, we aim to develop an intervention on gender-based violence (GBV) for health workers who provide HIV-related services to pregnant women in this setting. First, in order to gain in-depth contextual understanding of gender-based violence, we will conduct focus groups and in-depth interviews with pregnant women, men, and a variety of service providers (health, law enforcement, education, women's groups, and village leadership) in rural Nyanza Province, Kenya. We will use the knowledge gained to develop a GBV intervention for health workers, taking advantage of existing Kenyan GBV training programs. Finally, we will conduct a preliminary pilot of the adapted intervention to assess feasibility and acceptability. The results of this pilot study will form the basis for future research on a larger scale to examine the impact of addressing GBV on prevention of HIV/AIDS.