ABSTRACT Aggression and social withdrawal have long been of interest to personality psychologists The present article presents a longitudinal study of the development of children selected from a community sample who were high on aggression and withdrawal The selection of outcome variables is discussed, and outcomes during adolescence are described For both males and females, high aggressiveness was predictive of low intelligence, poor school achievement, and psychiatric problems For females, high aggressiveness was also predictive of general health problems High social withdrawal was predictive of poor school achievement Females who were high on withdrawal also had an elevated rate of abortions Individuals who were high on both aggression and withdrawal had relatively poor social competence, had general problems with behavior, had low intelligence, and were performing poorly in school