The aim of this study was to examine the prediction of adult behavioral and emotional problems from developmental trajectories of externalizing behavior in a 24-years longitudinal population-based study of 2,076 children. The adult psychiatric outcome of these trajectories has not yet been examined. Trajectories of the four externalizing behavior types: aggression, opposition, property violations and status violations were determined separately through latent class growth analysis using data of five waves, covering ages 4-18 years. We used regression analyses to determine the associations between children's trajectories and adults' psychiatric problems based on the Adult Self-Report. The developmental trajectories of the four types of externalizing behavior mostly predicted intrusive, aggressive and rule-breaking behavior in adulthood. Non-destructive behaviors in childhood such as opposition and status violations predict adult problems to a larger extent than destructive behaviors such as aggression and property violations. In general, children who develop through high-level trajectories are likely to suffer from both internalizing and externalizing problem behavior in adulthood, regardless the direction of change (i.e. increasing/decreasing/persisting) of the high-level trajectory. We can conclude that the level rather than the developmental change of externalizing behavior problems has a larger impact on adult outcome.