Why study Black gay men? What else is new to know about the life experiences of these men when so much HIV research has already been done? Why hasn’t the existing research resulted in meaningful changes in their health outcomes? These questions have driven many of our independent and collaborative studies aiming to study, articulate, and address the experiences of Black sexual minority men (SMM), including racism and stigma. This chapter describes how the unique confluence of racism and stigma comes to bear on the lives of Black SMM across the life course and why it matters that public health research continues to push the envelope towards improving health and quality of life for this population. Importantly, because racism and stigma are often tightly interwoven, both in the literature and across the socioecological experiences of Black SMM, some sections of this chapter will use these terms interchangeably. Although they are conceptually distinct, they frequently manifest for Black gay and bisexual men in similar ways, and their effects are often difficult to disentangle in both research and reality. Methodologically, disentangling their overlapping effects is also challenging, and there are practical and political limits to addressing racism and stigma. We therefore highlight not only the need for innovative research approaches but also the importance of critically assessing what is possible for public health initiatives without policy prescriptions when studying these salient factors, especially in the United States. Although much of the focus of this chapter is on those in the U.S., many of the dynamics described (i.e., sexuality-based stigma, racialized medical mistrust, and structural exclusion) resonate globally, affecting the lives of Black and other ethnic minority SMM across the African diaspora and beyond. The shared and distinct socioecological experiences regarding race- and sexuality-based exclusion highlight the collaborative transnational reach of anti-Blackness and sexuality stigma. This chapter calls for a more specific and realistic public health agenda that recognizes the interdependence of racism and stigma as socioecological determinants of health and realities that affect the life course possibilities for Black SMM.