In a test of Patterson's Coercion Theory with young children, 156 children (82 boys and 74 girls) were studied to assess the extent to which parenting and child variables, assessed at 18 months, would predict teacher ratings of externalizing child behaviors at age 5. Child playgroup behavior, parent coercion during home observations, and marital status each emerged as predictors, whereas child temperament, attachment classification, and gender did not. At age 5, the correlates of externalizing behaviors differed for boys and girls. Boys rated higher on externalizing behaviors by the teachers presented many problems in the home and school, whereas externalizing girls did not. In fact, girls rated higher on externalizing behaviors performed better on an intelligence test, yet the girls perceived themselves as less competent.