This comprehensive monograph addresses crucial issues in the protection of railway systems, with the objective of enhancing the understanding of railway infrastructure security. Based on analyses by academics, technology providers and railway operators, it explains how to assess terrorist and criminal threats, design countermeasures, and implement effective security strategies. In so doing, it draws upon a range of experiences from different countries in Europe and beyond. The book is the first to be devoted entirely to this subject. It will serve as a timely reminder of the attractiveness of the railway infrastructure system as a target for criminals and terrorists and, more importantly, as a valuable resource for stakeholders and professionals in the railway security field aiming to develop effective security based on a mix of methodological, technological and organizational tools. Besides researchers and decision makers in the field, the book will appeal to students interested in critical infrastructure protection.