In this article, Malcolm Watson, Kurt Fischer, Jasmina Burdzovic Andreas, and Kevin Smith describe and compare two approaches to assessing risk factors that lead to aggression in children. The first, the severe risks approach, focuses on how risk factors form a pathway that leads to aggressive behavior. Within this approach, an inhibited victim-aggressor pattern is hypothesized in which children who share certain characteristics--including high-conflict, low-cohesive families, high levels of harsh parental discipline, high levels of victimization by peers, and high behavioral inhibition--are at risk for developing defensive, reactive aggressive behaviors. The second, the cumulative effects approach, focuses on the accumulated effects of multiple risk factors in leading to aggressive behavior, irrespective of the particular risk factors involved. The authors assess both patterns longitudinally in a community-based sample that includes children from middle childhood to adolescence. They find strong evidence for both pathways.