'For more than a decade, Peter R. Neumann has been at the cutting edge of terrorism studies. Whether delineating the contours of this century's "new terrorism" or establishing the world's pre-eminent centre for the study of radicalisation and becoming that subject's foremost authority, Neumann has helped shape both the scholarly and popular discourse on terrorism and counterterrorism.' - Bruce Hoffman, Director of the Center for Security Studies at Georgetown University and author of Inside Terrorism, 'A vital contribution from one of Europe's leading thinkers on jihadist terrorism. Policy makers should heed his central warning: we will overcome this threat only when we tackle the sense of social marginalisation which plagues Muslim communities across Europe.' - Gilles de Kerchove, EU Counter-Terrorism Coordinator, 'Peter Neumann, a leading scholar of terrorism and radicalization, in his new book gives the reader an interesting, well written and deeply researched account of the new wave of jihadist terrorists that continue to be a central national security concern for the West.' - Peter Bergen, author of United States of Jihad: Investigating America's Homegrown Terrorists, "Peter R. Neumann's book is the most perceptive account of Islamic radicalization in today's world. In view of recent events in the United States and Europe, this is the book everyone needs to read." - Hassan Hassan, author of ISIS: Inside the Army of Terror, "Backed by original field work, Peter R. Neumann provides a balanced, clear-eyed and perceptive account of how the current terrorist threat evolved, what it is, and how we should address it. This highly accessible work should be of wide interest." - Richard Barrett CMG OBE, formerly Coordinator of the United Nations al Qaeda and Taliban Monitoring Team.