This volume provides a critical assessment of the liberties of citizens and others in the European Union (EU) and the different ways in which they are affected by the proliferation of discourses, practices and norms of insecurity enacted in the name of the safety of the citizen and collective security. It analyses from an interdisciplinary perspective the impacts of new techniques of surveillance and control of human movements over the liberty and security of the individual. The book offers a study of illiberal practices of liberal regimes in the field of security, and the relationship between the internal and external effects of these practices in an increasingly interconnected world, as well as the effects in relation to the place of the EU in this world. The volume presents the final results of the CHALLENGE research project (The Changing Landscape of European Liberty and Security) - a five-year project funded by the Sixth Framework Programme of DG Research of the European Commission. `Delivering liberty' would seem an obvious task for democracies, but the book -and the CHALLENGE research project that originated it - explores the reasons why this remains a challenge. It interrogates the conceptual, empirical and normative relations between liberty and security and does so by fruitfully contesting the boundaries between different research disciplines and by engaging with policy makers and the public. Angela Liberatore, Directorate General for Research, European Commission This is the acme of policy-relevant, intellectually coherent scholarship. It explores the challenges facing the EU in providing effective security at, within, and even outside its borders while preserving the personal and societal liberty at the core of democracy Largely implicit suggestions that a zero-sum relationship between security and liberty can and should be avoided underlie both the framework and the meticulously objective analyses of the several chapters. Martin O.