I focus on the study of social development with a developmental psychopathology orientation. My main research activities attempt to understand the development of subtypes of aggressive behavior in children. Specifically, my colleagues and I have been exploring the development of relational and physical aggression (and peer victimization) during early and middle childhood. Current research also examines the development of both forms (relational and physical) and functions (proactive and reactive) of aggression. We have also been developing and testing the efficacy of an intervention for aggressive behavior among young children.