This book offers a comprehensive systematic analysis of the European Union's Early Warning System (EWS) for subsidiarity, which was introduced by the Treaty of Lisbon. The book includes both a detailed theoretical analysis of the EWS as well as an assessment of how national parliaments have responded to EU legislative proposals under the system. Philipp Kiiver explores whether the EWS could function as a mechanism of legal accountability offering a partial remedy to the European Union's much-discussed accountability deficit. The Early Warning System for the Principle of Subsidiarity provides an overview of the historical developments of national parliamentary involvement in the EU and also considers the broader implications of the EWS, including its relationship to democracy and legitimacy.

The book will be of particular interest to academics and students of EU Law, Constitutional Law and Political Science.