Joseph E. Oliver, PhD, is a consultant clinical psychologist and joint director of the Cognitive Behavioural Therapy for Psychosis Post Graduate Diploma program at University College London. He also works within a North London National Health Service Trust, developing training and delivering interventions for people with psychosis. He is director for Contextual Consulting, a London-based consultancy offering ACT-focused training, supervision, and psychological therapy. Joseph is an Association for Contextual Behavioral Science (ACBS) peer-reviewed ACT trainer, and regularly delivers ACT teaching and training in the UK and internationally. Along with Eric and Louise, he is coeditor of the book, Acceptance and Commitment Therapy and Mindfulness for Psychosis and coauthor of the self-help book, ACTivate Your Life.