The role of political psychology is often neglected in attempts to understand terrorist networks and radicalisation. This essay will demonstrate how, when utilised correctly, political psychology can shed light on the inner workings and development of terrorist networks. Existing literature on the political psychology of terrorist networks is relatively limited and underrepresented compared to vast amounts of work regarding political science. This paper seeks to fill this knowledge gap by providing an analysis of how political psychology can contribute to the understanding of the inner workings and development of a terrorist network. This essay will highlight the role of political psychology in the provision of insight into: the thought processes and rationale of individuals and terrorists networks; the shift from individual to a group identity via complex and gradual radicalisation; how networks solidify their memberships’ dependency; the role of competition in hardening group solidarity and radicalisation, and finally how political psychology can reveal the mechanisms that terrorist networks utilise in order to overcome ‘mainstream-morals’ and disengage from self-censure (i.e. ‘the act of killing’). This research paper will contend that in conjunction with other fields (e.g. political science, sociology), psychology is a necessary and critical tool in understanding the intricacies surrounding the development and activity of terrorist networks.