The current study tests whether the presence of callous-unemotional (CU) traits designates a group of children with conduct problems who show an especially severe and chronic pattern of conduct problems and delinquency. Ninety-eight children who were selected from a large community screening of school children in grades 3, 4, 6 and 7 were followed across four yearly assessments. Children with conduct problems who also showed CU traits exhibited the highest rates of conduct problems, self-reported delinquency, and police contacts across the four years of the study. In fact, this group accounted for at least half of all of the police contacts reported in the sample across the last three waves of data collection. In contrast, children with conduct problems who did not show CU traits continued to show higher rates of conduct problems across the follow-up assessments compared to non-conduct problem children. However, they did not show higher rates of self-reported delinquency than non-conduct problem children. In fact, the second highest rate of self-reported delinquency in the sample was found for the group of children who were high on CU traits but without conduct problems at the start of the study.