During the course of the past four decades, developmental psychopathology has emerged as a new science that integrates various disciplines, the efforts of which had previously been distinct and separate. The distinctiveness and uniqueness of a developmental psychopathology approach lie in its focus on normal and abnormal, adaptive and maladaptive, developmental processes. A developmental analysis presupposes change and novelty, highlights the critical role of timing in the organization of behavior, underscores multiple determinants, and cautions against expecting invariant relations between causes and outcomes. A developmental analysis is essential for tracing the roots, etiology, and nature of maladaptation so that interventions may be timed and guided as well as being developmentally appropriate. Moreover, a developmental analysis proves useful for discovering the compensatory mechanisms – biological, psychological, and social-contextual – that may promote resilient functioning despite the experience of significant adversity. Inherent to a developmental psychopathology approach is a commitment to the importance of applying knowledge of normal development to the study of typical populations. Even prior to the emergence of a mental disorder, certain pathways signify adaptational failures in normal development that probabilistically forebode subsequent psychopathology. The approach suggested by a developmental psychopathology framework requires a comprehensive assessment of functioning including multidisciplinary, multidomain, multilevel, and multicontextual measurement strategies. Additionally, developmental psychopathology is a lifespan perspective, because it is only by examining a range of conditions from infancy through adulthood that developmental continuities and discontinuities can be elucidated fully.