The main aim of the study relates to the links between bullying and victimization on the one hand and reactive and proactive aggression on the other. In addition, we also investigated stability and incidence of bullying and victimization. At age 7,236 children were rated on bullying and victimization using peer reports. At age 8, 242 children were rated again. Two hundred and fifteen children (114 girls and 101 boys) were present at both time points. Reactive and proactive aggression was assessed by teachers. The results showed that bullies and bully/victims were both reactively and proactively aggressive, while victims were only reactively aggressive. A moderate degree of stability of bullying and victimization was found, with bullying being more stable than victimization. Boys were more often bullies than girls and more stable than girls in victimization. Stable victims and stable bully/victims were more reactively aggressive than their unstable counterparts. The relevance of the outcomes to preventing future maladjustment and suggestions for further research are discussed.