Engaging boys (up to age 18) is a critical yet under-explored area of GBV prevention in emergencies. This annotated bibliography provides an overview of relevant literature, evaluations, and programmatic examples for engaging boys in GBV prevention programming with a focus on high and middle-income settings and—to the extent knowledge exists— humanitarian contexts. Building on an emergent body of global literature on male engagement for GBV prevention, the bibliography begins with an overview of evidence and lessons learned in work with boys to prevent GBV generally, and then focuses on examples of specific types of programs, such as community-based social norms change; bystander interventions; school-based programming; peer education; and sports- and play-based programming. This information is meant for GBV practitioners working in emergency settings who are seeking to work with boys as allies in GBV prevention.