Heterogeneity of re-offending patterns was studied in a group of 287 male early onset offenders who were first arrested before age 12. By combining data on the frequency and severity of offending as registered by the police over a 5-year follow-up period, three delinquent trajectories were identified; low, escalating, and high level re-offenders. Predicting group membership by individual and environmental characteristics known to the police at the time of the first arrest proved difficult. Compared to low level re-offenders, escalators were older and more often came from disadvantaged neighborhoods. High level re-offenders were also older at onset, more often had a non-Western ethnic background, and initially committed more vandalism. Furthermore, at the first police encounter, the police reacted more severely towards those who later became high level re-offenders. Finally, high and escalating re-offenders more often had other adverse outcomes, such as criminal victimization and Child Welfare Agency involvement