HIV-related stigma negatively affects prevention and care, and community-based interventions are needed. Here we describe the development of a multi-ethnic, faith-based intervention to reduce HIV stigma that included: educational workshops on HIV, testing, and stigma; peer leader workshops using role plays and drawing on principles of motivational interviewing; a pastor-delivered sermon on HIV that incorporated theological reflection and an imagined contact scenario; and congregation-based HIV testing events. Lessons learned include: partnership development is essential and requires substantial investment; tailoring intervention components to single race-ethnic groups may not be preferable in diverse community settings; and adapting testing processes to be able to serve larger numbers of people in shorter time frames is needed for congregational settings. This development process successfully combined the rigorous application of social science theory and community engagement to yield a multifaceted HIV stigma reduction intervention appropriate for Protestant and Catholic churches in African American and Latino communities.