In this article, we use data from the Columbia County Longitudinal Study [Huesmann et al., 1984, 2006], a prospective study tracking the development of aggression of an entire county’s population of third-grade students in 1960 from age 8 to 48. We examine several related questions about the long-term consequences of aggressive and antisocial behavior in childhood and adolescence. First, we examine the continuity of aggressive behavior and look at the extent to which continuity and change in those behaviors conform to ideas about life-course-persistent and adolescent-limited behaviors. We also test whether continuity of aggressive and antisocial behavior is a consequence of a few high-aggressive participants remaining high as some have suggested or more a consequence of a general tendency for people to retain their relative position in the population as they mature. Second, we examine the extent to which different patterns of continuity in aggressive and antisocial behavior from middle childhood to early adulthood (e.g., life-course-persistent low or high aggression, adolescent-limited aggression) predict negative (e.g., criminality) and positive (e.g., health, educational and occupational success) outcomes in middle adulthood.