Counter-terrorism law and policy has been prominent and widespread in the years following 9/11, touching on many areas of everyday life from policing and border control to financial transactions and internet governance. The European Union is a major actor in contemporary counter-terrorism, including through its development of counter-terrorism laws for application within the Union. This book undertakes a multi-disciplinary and empirically informed analysis of the impact, legitimacy and effectiveness of EU counter-terrorism.Taking into account legal, societal, operational and democratic perspectives, this collection connects theoretical and practical perspectives to produce an interdisciplinary and multi-stakeholder study of how we might measure and understand the impact, legitimacy and effectiveness of EU counter-terrorism. Bringing together a select group of experts in the field, particular emphasis is placed on understanding the practical experience of implementing and assessing these measures gathered from and with end users, including law-makers, policy-makers, security services, industry partners and civil society.This edited collection will be of great relevance to scholars and policy makers with an interest in counter-terrorism law, EU law and security studies.