This chapter takes an ecological approach to understanding the emergence of psychopathology in adolescence with a focus on the role of puberty. It reviews the state of knowledge regarding measurement of puberty, links between puberty and psychopathology, and possible underlying mechanisms including neurodevelopmental pathways as well as social and environmental influences. Disparities by race/ethnicity, socioeconomic status, gender, and sexual/gender identity are also discussed. It concludes by reviewing the knowledge and methods of four promising areas of future research in developmental psychopathology during adolescence. First is the biological basis of mental and behavioral health with a focus on the interplay between pubertal hormones and brain development. Second is translation of links between pubertal development, and behavioral and psychological health to the pediatric setting. Third is the role of technological advances in facilitating research and shaping the adolescent experience. Finally, research on laws and policies that have implications for adolescent mental and behavioral health are discussed, including changing drug laws and policies related to marriage equality. Throughout the chapter, the focus is on providing practical recommendations for researchers. The ecological perspective provides a multilevel framework for understanding the development and prevention of psychopathology as well as the reduction of disparities for vulnerable populations.