Traditionally, terrorism and counter-terrorism studies have been highly specialized fields, confined predominantly to the subject areas of political science, international relations and terrorism studies. Astonishingly perhaps, over the last ten years or so, there has been an enormous increase in the number of academics writing about terrorism and counter-terrorism from a wide range of different subject disciplines, including the arts, humanities and social science fields, such as policing studies, sociology, history, criminology, psychology, Islamic studies, religious studies, theology, law, anthropology and philosophy, alongside terrorism, critical terrorism studies, international relations and political science. Added to this, engineering, computer science and other ‘hard’ sciences have also increasingly focused upon questions of national security through developing and testing various new technologies that can be used for surveillance, risk identification and detection among other purposes.