Meaningful adolescent and youth engagement is an inclusive, intentional, mutually-respectful partnership between adolescents, youth, and adults whereby power is shared, respective contributions are valued, and young people’s ideas, perspectives, skills, and strengths are integrated into the design and delivery of programs, strategies, policies, funding mechanisms, and organizations that affect their lives and their communities, countries, and world. Meaningful adolescent and youth engagement recognizes and changes the power structures that prevent young people from being considered experts regarding their own needs and priorities, while also building their leadership capacities. Young people includes ‘adolescents’ ages 10-19 and ‘youth’ ages 15-24 (based on the WHO definition) regardless of socioeconomic status, ethnic identity, sexual orientation, gender identity and expression, sex characteristics, marital status, religion, disability, political affiliation, or physical location.