In the aftermath of the invalidated Data Retention Directive, the Court of Justice of the European Union (CJEU) published extensive case law that shaped the rules, requirements, and safeguards on the retention of traffic and location data and their subsequent access for law enforcement purposes in accordance with EU law. Against this backdrop, Data Retention in Europe and Beyond unites leading scholars and practitioners to offer a cutting-edge and multifaceted analysis of issues relating to data retention. The chapters in this book explore the development of the EU case law, the interaction with European Court of Human Rights (ECtHR) jurisprudence, the interplay between data retention and mass surveillance, the proportionality principle in the CJEU jurisprudence rulings, and data retention in the proposed ePrivacy Regulation. The book offers eleven country-specific analyses of European Member States as well as chapters on the data protection regimes of India, Japan, and the US.