This book focuses on the attempt to introduce biometric identity cards in the UK from 2004 to 2008. It provides an in-depth study of the UK case and the challenges of implementing a new identity system. The book also attempts to map identity policy challenges globally by reviewing policies in other countries. While focused on the UK, the book aims to establish broader themes in identity policies worldwide and examines the complex relationship between policymaking and borderless technology. It highlights the difficulties of enforcing technology policies and the challenge of addressing multiple identity policy purposes with a single policy.