Three subgroups of kindergarten boys (Stable conduct disordered‐hyperaetive (SCDH), Stable conduct disordered (SGD). Stable non deviat control(SC)) were‐ defined and Followed up three, four and five years later in primary schools. Using assessments From multiple informants (teachers, mothers peers, self), the results showed that SCDH boys were more hyperactive (i.e. overactive inattentive) and displayed a greater diversity of conduct problems in school and home at follow‐up compared to other groups. These results, and the fact that during early adolescence SCDH boys tend to develop a worse prognosis than SCD boys suggest that they should be distinguished.