The developmental psychopathology approach helps us to understand why some individuals develop mental disorders and other individuals follow a different path. Some of the early applications of the developmental psychopathology model took place in the 1970s. The common, unifying principle of developmental psychopathology is the integration of understanding “normal” and “abnormal” behavior, traits, and processes. Understanding variation in normal/abnormal behaviors across development may improve understanding of those at risk for mental health problems. The principle of developmental psychopathology is that research should examine multiple levels of analyses to include biological, individual, familial, social, and cultural levels. One key principle of developmental psychopathology is examining both risk and protective factors to understand pathways of risk and resilience. The chapter provides a brief overview of the methods used to study developmental psychopathology. It discusses how developmental psychopathology encompasses a wide range of disciplines and methods to answer big questions.