Peers have significant influence on identity, health behaviors, and life course outcomes across populations. For Black sexual minority men (SMM), peers can serve as surrogate families that provide support and guidance that is generally lacking in traditional familial, social, or clinical contexts. Beyond emotional connection, peers also function as crucial health influencers and community health interventionists for this group globally. This chapter examines the multidimensional influence of peers on the lives of Black SMM, focusing on their dual ability to affect health behaviors and reinforce risk. Drawing from targeted sexual health studies (which constitute most of the available literature on this population) and multidisciplinary frameworks, the chapter investigates how peers operate within social networks and influence community health attitudes, behaviors, and outcomes. Special attention is given to peer-based intervention models such as popular opinion leaders and peer change agents who promote healthy behaviors as in-group health communicators. The chapter also critiques existing peer-based interventions and examines the ideal in-group attributes that can enhance credibility, relatability, and health influence for effective “peerness.” A case is made for designing peer-based interventions that are attuned to the margins of culture, sexuality, and age and that recognize peers as essential for health promotion for Black SMM.