A persuasive case is presented by Ringeisen, Henderson, and Hoagwood (2003) for the significance of school contexts in child development and the potential for improving child mental health and achievement through more sophisticated, integrative, multilevel, and multidisciplinary models of how schools and children change. This perspective reflects a transformation taking place in models of psychopathology in children and what to do about it, with implications for research, policy, treatment, and prevention efforts involving schools. This article underscores three fundamental tenets of developmental psychopathology with relevance to school-based practices and research: (1) children are living systems whose lives reflect complex interactions with other systems, including schools, which in turn are embedded in larger systems; (2) understanding positive adaptation and development is important for preventing and treating problems, particularly among children at risk for psychopathology; and (3) more complex approaches are required in order for interventions or research to accommodate the embedded multi-system realities of children's lives, and these approaches require collaborations at a much earlier and deeper level. (Contains 1 figure.)