Posttraumatic stress disorder (PTSD) is one of the anxiety disorders with particularly debilitating effects due to flashbacks and hypervigilance in daily life. Treatments commonly focus upon either pharmacological or psychotherapeutic modalities, but there is often a need to merge both of these approaches to deal effectively with the somatic, as well as the psychological, symptoms of PTSD in particular clients. This case study reports the application of a combined approach, using both client-centred counselling plus biofeedback of respiratory sinus arrhythmia to train the client to control his exaggerated sympathetic nervous system responses. Results indicated that both physiological and psychological measures of PTSD in this client significantly reduced during the seven treatment sessions.