Positive youth development represents an emerging emphasis in developmental thinking that is focused on the incredible potential of adolescents to maintain healthy trajectories and develop resilience, even in the face of myriad negative influences. This volume discusses the theory, research, policy, and programs that take this strength-based, positive development approach to diverse youth. It examines theoretical ideas about the nature of positive youth development, and about the related concepts of thriving and well-being, as well as current and needed policy strategies, best practice in youth-serving programs, and promising community-based efforts to marshal the developmental assets of individuals and communities to enhance thriving among youth.