While many factors affecting policy convergence in the environmental field have been identified, we still have limited knowledge on their distinctive impact. In view of this constellation, the project concentrates on two major objectives. First, we will analyse the extent to which there is actually a convergence of national environmental policies in Europe over time. Second, we will investigate the specific impact of international institutions and trade on the scope, speed and level of convergence. In addressing these objective, the project aims to offer insights to policy-makers on how to anticipate the impact and interaction effects of these factors in order to improve environmental policy-making in Europe.