Degree Name

Doctor of Philosophy


School of Law


This thesis examines the factors, which lead to the emergence of terrorist groups and the evolution of their organisational structure. The three case studies used within this thesis examine terrorist groups as complex adaptive systems. Historically, the only group, which has been studied as a complex adaptive system, is Al Qaeda. This study builds on this work by examining three cases of historical terrorist groups: the Provisional Irish Republican Army, Weather Underground Organisation, and Kosovo Liberation Army, in an attempt to ascertain whether the concept of complex adaptive systems can be generalised to a broader range of groups.

The thesis found the potential size of the pool of recruits available to a group, was directly related to the amount of homophily the target community shared with the group. It was determined the amount of homophily the community shared with the group, was related to the environment. It was found the group’s structure was a function of the physical length of the communications channels, the security of the channels of communications and the group’s size, all of which were dictated by the environmental conditions across the conflict space.

The thesis argues the environment in which they emerge, drives the creation of these types of groups. The thesis further argues the structure these types of groups adopt is also a response to the environmental conditions. The thesis utilised the principles of preferential attachment (homophily) to describe how the environment affected the emergence of the group, its size, and its structure. The group’s structure is defined by the topology of its communications network.

The case studies demonstrated the group structure was dynamic, was dependent on size, geographic dispersion, and lacked day-to-day centralised control. The structure of the groups was consistent with those of complex adaptive systems. The elements of the groups acted in parallel, working towards the same goal. The structure of the group was built on pre-existing social structural elements, which acted as building blocks for the higher levels organisation. The various elements of the group adapted to meet the environmental challenges presented to the group over its life cycle, which led to the structure of the group evolving over time. It was found that groups, which were traditionally thought to maintain hierarchical structures, behaved more like networks, because of limitations placed on the communications channels by the environment. This led the groups to maintain a decentralised and distributed leadership model, where each of the elements worked independently towards the group’s goal. This network structure, model of leadership and control, was found to be consistent with a complex adaptive system.

Even though all three case studies could be described as complex adaptive systems, further work will be required to ascertain whether this concept can be generalised to a greater diversity of groups. This analysis indicated this model holds promise and could assist in combating these types of groups. An understanding of the variables provides insight into methods, which could be used to mitigate the factors involved in the emergence of these types of groups.



Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.