How Have EU Legislators Established EU Agencies With Enforcement Tasks? Case Studies of the European Aviation Safety Agency and the European Medicines Agency

European Union (EU) policies were long enforced according to a well‐established framework in which member state governments made legislative, administrative and operational arrangements for realizing policies made in Brussels. EU legislators, however, are increasingly creating EU agencies to help enforce EU policies. This article attempts to explain this puzzling development, as it examines how the establishment of EU enforcement agencies by EU legislators relates to the well‐established role of member states. This article relies on case studies of the European Aviation Safety Agency (EASA) and the European Medicines Agency (EMA). These case studies show that, during the establishment of those agencies, the member state enforcement framework provided institutional stability on the one hand yet facilitated institutional change on the other. This institutionalist account of EU agency establishment supplements functional and political ones that have so far prevailed in the academic discourse.