We present the process of developing a social marketing campaign to promote HIV testing with Black and Latina women living in neighborhoods with high rates of HIV. We developed partnerships with organizations serving women at high risk for contracting or transmitting HIV as well as with experts in prevention, marketing, and research. Focus groups with community organizations’ staff members helped create motivational messages. These data led us to focus on health promotion attitudes toward enhancing well-being rather than on fear-based messages about disease and risk behaviors. Additionally, we determined that to shape norms and self-efficacy, messenger images should be women that the focus audience would identify with as a model of their “best self”—attainable and positive. A series of messages were then pretested to Latina and Black women receiving services at the partner organizations. They confirmed that they did not want to read negative messages or see portraits of women representing their community in a stigmatizing way. Women also related barriers to testing such as fear of medical providers, stigma, and child welfare intervention, which would impact the costs and benefits of testing. Motivations to get tested included availability of health-care services in addition to testing and a “strong/positive” messenger for testing. Materials were distributed in locations that would be coordinated with HIV prevention services of testing, education, and linkage to care. A small-scale evaluation indicated that 14% of women recognized the campaign and 33% of those women said it influenced their behavior.