During the last decade the rapid growth of justice and home affairs as an internal policy making domain of the European Union has led to the Union emerging as an increasingly important international actor in this field. This book covers the institutional and legal framework of the external dimension of EU justice and home affairs; issues of policy interaction as well as specific challenges; policy responses and results in the fields of migration policy; judicial cooperation; counter-terrorism; and cooperation with major international partners. Taking into account the changes introduced by the Treaty of Lisbon as well as the priorities set by the 2010-2014 Stockholm Programme the book provides an in-depth exploration of the political and legal dynamics of a major new dimension of the EU.