Abstract
This paper aims to explore the issue of unintended consequences as the key underlying theme that explains the incremental integration of policies in the EU, with a particular focus on the issue of environmental protection. The theoretical background of the present research is provided by two of the main schools of thought that, in different historical contexts, have theorized unintended consequences as a relevant interpretative/analytical tool for European integration, namely neo-functionalism and neo-institutionalism. The paper focuses on three distinctive moments of the EU environmental policy: the first steps in the 1970s, the change of regulatory paradigm during the 1990s, and the EU leadership role in global environmental policy. The main argument is that while neo-functionalism can give a convincing account of the initial phases of EU environmental policy, neo-institutionalism offers a persuasive framework to understand the consolidation phases of the policy.