Prime Minister Malcolm Turnbull’s recent initiative seeking to investigate the link between mental health and extremism is long overdue. We have moved beyond the hypothetical circumstance of domestic terrorism into a battleground fought in schools and in virtual worlds. The divergent threat currently posed by extremists necessitates a review of what we have learned, if anything, of the individuals involved in such activity. The aim, of course, is to enhance the effectiveness of preventative activity. From a psychological perspective, aberrant behaviour is most readily explained by patterns of ‘disordered thinking’. Extremism falls within this description, irrespective of its manifestations. The connectedness of the behaviour to religion confuses an issue that would otherwise be readily attributed to mental disorder. That is, humankind has long rationalised violent behaviour conducted under the auspice of ‘religious expression’. Current intervention initiatives, within Australia, are heavily reliant on government-managed programs and continue to reflect a basic understanding of the extremist mind set. If it is accepted, as it should be, that extremism remains, essentially, psychological dysfunction, what lessons can be applied to current intervention strategies? How the field of psychology has applied years of research remains particularly instructive. The classic disordered patient, often presenting through emotional disturbance such as anger, anxiety or depression, typically requires sustained engagement with a skilled practitioner. Motivation to improve is almost always the foundation of constructive engagement. Although the context and premise of engagement differs substantially, the principles are almost universally applied when presented with a ‘radicalised’ individual. The obvious difficulty lies in an extremist’s motivation to change. This is the point at which most de radicalisation programs fail. Changing entrenched, self-serving