Abstract
This entry focuses on the allocation of powers in environmental matters in multilevel systems, i.e. systems that have decision-making authorities at different government levels. In the first part, this issue is examined from a theoretical point of view, with reference to the scholarly work concerning environmental federalism. In particular, criteria on how to divide environmental competences, the opportunities and challenges of such a division, and the need for coordination and conflict-resolution mechanisms are discussed. In the second part, two national European cases, Spain and Italy, are examined with a view to understanding how powers are concretely divided, how coordination is concretely achieved, and how conflicts are concretely solved. National cases are preceded by the analysis of how multilateral decision-making in environmental matters is realized in the European Union.