This presentation reviews the major neurobiological systems that are perturbed in PSTD. These include the fear network, default mode network, sympathetic HPA axis, the arousal/activation systems of the brainstem and the salience/attention networks of the limbic-cortical system. Each of these networks plays a specific role in PTSD symptomatology, contributing to its complex and disturbing phenomenology. The talk reviews how quantitative EEG can provide insight into the functioning of these systems, and can be used with other profile measures in designing treatment protocols. There will be a brief review of the different neurotherapeutic approaches that can assist in this regard as part of the treatment mix, with examples.