“This phenomenal book showcases contributions from leading experts in online violent extremism, presenting the most up-to-date research and insights available for addressing today’s rapidly evolving threat landscape. It offers readers a clear and accessible guide to a very complex subject, making it an essential resource for anyone who wants to stay at the cutting edge of research in online violent extremism.”John Horgan, Department of Psychology, Georgia State University, USA“This essential handbook provides an expansive and timely analysis of the digital landscape, synthesising the latest evidence on diverse methodologies, online contexts, and emerging technologies into a single, definitive volume. Covering everything from research ethics to ideological drivers and platform-specific dynamics, it provides an unparalleled foundation for understanding the breadth of contemporary online violent extremism.”Sarah Marsden, Director, Handa Centre for the Study of Terrorism and Political Violence, University of St Andrews, UK“A timely and authoritative contribution, it offers a sweeping, interdisciplinary examination of how digital technologies have reshaped extremist movements and the global response to them. Bridging theory, policy, and practice, it is an indispensable resource for scholars, practitioners, and policymakers seeking to understand and anticipate the evolving dynamics of violent extremism in an increasingly complex online ecosystem.”Paul Gill, Professor in Security and Crime Science, UCL, UK“Earlier technological revolutions like the printing press and the mass communication of radio and television restructured both human consciousness and social realities. The digital age is doing it again, in breathtakingly complex ways. This brilliant handbook, with stunning contributions from world-leading scholars, illuminates not just how violent extremists have leveraged digital technologies, but how those technologies themselves have enabled new forms of violent extremism and new challenges for addressing the harms they promote. Violent extremism will never be the same again, and this collection helps us understand why. Essential reading for everyone interested in the nexus between violence, ideology, communication and human interactions with technology.”Michele Grossman, Deakin Institute for Citizenship and Globalisation, Deakin University, Australia“An absolutely stellar line-up of contributors have come together here to provide a wide-ranging and utterly comprehensive volume on online violent extremism. The result is a must-read for anyone interested in understanding and responding to this growing, critically important issue. Ignore at your peril.”Andrew Silke, Chair in Criminology, Royal Holloway, UK