In this study, we examined how aggression, prosociality, and withdrawal, as reactions to interpersonal conflict situations, manifest themselves in pre-, mid-, and late adolescence (N = 2594). The subjects filled out a questionnaire that contained a description of two everyday problem situations with a set of problem-solving strategies. The results showed that aggression develops curvilinearily and that both prosociality and withdrawal decrease with age. In addition, both direct and indirect aggression, as well as withdrawal, were found to be more typical among boys than among girls whereas, in late adolescence, prosociality was more typical among girls. The most often used strategy in preadolescence was prosociality and in midadolescence, aggression. In late adolescence, girls used prosocial and withdrawal strategies most whereas the most often used strategy among boys was aggression.