Mental, emotional, and behavioral (MEB) disorders, including mental illness and substance use disorders, affect every U.S. population group, community, and neighborhood. Existing infrastructure focuses more on responding to MEB crises, through treatment and recovery, rather than preventing them through evidence-based policy approaches and programs. Prevention services that do exist are insufficiently funded and fragmented.Blueprint for a National Prevention Infrastructure for Mental, Emotional, and Behavioral Disorders focuses on building and sustaining a comprehensive prevention infrastructure for MEB disorders as a whole. Conclusions and recommendations of this report focus on closing research gaps, supporting an MEB disorder prevention workforce, ensuring adequate data to support prevention and reporting, establishing clear governance, securing sustainable funding, and enacting evidence-based policies.