David Westbrook is a Consultant Clinical Psychologist, and was Director of Oxford Cognitive Therapy Centre (OCTC) until June 2012, when he stepped down to spend more time on writing. Before training as a clinical psychologist he was a psychiatric nurse, eventually becoming the nurse in charge of a specialist behaviour therapy unit in London. This led on to an interest in cognitive therapy, which has included training from many of the world's leading CBT therapists. He has been practicing CBT for over 25 years and currently works part-time in OCTC, doing training, supervision and research; and part-time as an NHS clinician, providing a service for patients with severe and complex problems. He is BABCP-accredited as a therapist, supervisor and trainer.