This conclusion presents some closing thoughts on the concepts covered in the preceding chapters of this book. The book provides an overview of the ways in which the academic literature has tended to characterise the role of fear and psychological violence in the process of political terrorism. It identifies gaps in knowledge and key questions about hostile intent and counter-terrorism that provide a basis for future research. The book presents an overview of the theoretical foundations pertinent to the investigation of deception and speech. It outlines user requirements methods/approaches applied to a rail case study in order to identify organisational responses to security threats. The book also explores publicly visible counter-terrorism measures, uncovering the strategic role of design in creating controlled disruption in public spaces to reduce threat while at the same time reducing anxiety. It focuses on armed assaults on educational institutions, the frequency of which has increased sharply since 2003.