The willingness to solve conflicts without violence and to strive for a reconciliation of interests is of central significance for the continued existence of democracies. In this paper, we aim to analyze school-related determinants of adolescents' conflict behaviour. Models predicting the conflict styles of "integrating", "dominating", "avoiding" and "obliging" were developed drawing on different school climate and school development variables. At the individual level, almost all our hypotheses were confirmed. The highest correlations were found between an open classroom climate and the participation in a class council on the one hand, and an integrating conflict style on the other. On the class level however, most of the anticipated effects did not turn out to be significant. We hope that by providing information about different school climate and school development variables' impacts on adolescents' conflict styles, we can contribute to a more effective promotion of constructive conflict behaviour in adolescents.