HIV-related service delivery gaps remain in many regions of the world, and HIV-related stigma constitutes a major barrier to filling them. Latin America is no exception. In addition to high levels of stigma toward and among PLWH, there is pervasive stigma against populations most affected by HIV, for example, young men who have sex with men (MSM). Mitigating HIV-related stigma as well as other stigmas that intersect with HIV-related stigma will be critical to meeting testing and treatment targets, and improving health outcomes in Latin America. We will evaluate the feasibility of a social marketing public health strategy for reducing HIV-related stigma, and associated intersectional stigma, among young people in an urban Latin American setting. We will conduct focus groups with key stake holders to learn which messages they perceive to be most important for stigma reduction, which types of intersectional stigma should be considered and what they would like to see changed as a result of the intervention. Then, drawing on theory-based approaches for stigma reduction, information dissemination, and health communication, we will create a series of locally tailored multimedia content (e.g., short videos, music videos, and memes). To evaluate potential efficacy, we will conduct a randomized online social marketing study in which we assign users to view our HIV-related content or a control product and measure changes in stigmatizing opinions related to HIV and intersectional stigmas. Finally, we will recruit societal influencers to transmit our content through their social media networks and examine whether young people exposed to the social media content experience a greater reduction in perceived stigma relative to controls who are not exposed to the intervention.