Researchers seeking to engage in projects related to Tribal communities and their citizens, lands, and non-human relatives are responsible for understanding and abiding by each Tribal nation’s research laws and review processes. Few studies, however, have described the many diverse forms of Tribal research review systems across the United States (US). This study provides one of the most comprehensive examinations of research review processes administered by Tribal Research Review Boards (TRRBs) in the US. Through a systematic analysis, we consider TRRBs’ (...) online presence, online documentation, and themes across documents, for five entity types: Tribal nations and Tribal consortiums, Tribal colleges and universities, Tribal health organizations, Indian Health Services, and other Tribal organizations. Results include an assessment of online presence for 98 potential TRRBs, identification of 118 publicly available online documents, and analysis of 41 themes across four document types: Tribal research codes and TRRBs’ guidelines, applications, and post-approval documents. Altogether, this research provides a macro-level analysis of the most common types of TRRBs in the US in an effort to increase researchers’ understanding of these important processes as they prepare to ethically engage Tribal communities in research. These results aim to empower Tribal decision makers as they align their TRRBs’ online visibility and documentation with community priorities and strengthen their protections for the rights and wellbeing of their citizens and community. Ultimately, by expanding our knowledge of TRRBs across the US, this contribution seeks to uphold Tribal sovereignty in research and promote ethical approaches to research with Indigenous communities. (shrink)