John Horgan is Professor of Global Studies and Psychology at Georgia State University. Professor Horgan has a PhD in applied psychology, and his research examines the psychology of terrorist behaviour. His most recent book is The Psychology of Terrorism 2nd Edition. His current research projects examine individual trajectories into, and out of, terrorism; radicalisation and de-radicalisation; children’s involvement in terrorism; self-concealment in terrorist groups; and the relationship between religious conversion and radicalisation to violent extremism. He also previously served as an ICCT Editorial Board member.