Religious organizations may be uniquely positioned to address HIV by offering prevention, treatment, or support services to affected populations, but models of effective congregation-based HIV programs in the literature are scarce. This systematic review distils lessons on successfully implementing congregation HIV efforts. Peer-reviewed articles on congregation-based HIV efforts were reviewed against criteria measuring the extent of collaboration, tailoring to the local context, and use of community-based participatory research (CBPR) methods. The effectiveness of congregations' efforts and their capacity to overcome barriers to addressing HIV is also assessed. We found that most congregational efforts focused primarily on HIV prevention, were developed in partnerships with outside organizations and tailored to target audiences, and used CBPR methods. A few more comprehensive programs also provided care and support to people with HIV and/or addressed substance use and mental health needs. We also found that congregational barriers such as HIV stigma and lack of understanding HIV's importance were overcome using various strategies including tailoring programs to be respectful of church doctrine and campaigns to inform clergy and congregations. However, efforts to confront stigma directly were rare, suggesting a need for further research.