Maureen L. Whittal, PhD, is a private practice psychologist at the Vancouver CBT Centre in Canada. She is also Clinical Associate Professor in the Department of Psychiatry and Adjunct Faulty in the Department of Psychology at the University of British Columbia, and is on the teaching faculty for the International OCD Foundation. Dr. Whittal has been engaged in clinical and research work in obsessive–compulsive disorder (OCD) since getting her start in 1986 as an undergraduate research assistant for Dr. Jack Rachman. She is a Fellow of the Association for Behavioral and Cognitive Therapies, the Academy of Cognitive Therapy, and the Canadian Association of Cognitive and Behavioural Therapies, and a former editor of Cognitive and Behavioral Practice. Dr. Whittal provides lectures and workshops on OCD to professionals across North America, the United Kingdom, Australia, and Europe.

Adam S. Radomsky, PhD, is Professor of Psychology at Concordia University in Montréal, Québec, Canada, where he is Director of the Anxiety and Obsessive–Compulsive Disorders Laboratory and a Core Member of the Centre for Clinical Research in Health. Dr. Radomsky is known for his research on cognitive, behavioral, and emotional aspects of obsessive–compulsive disorder (OCD) and related disorders, including the role of beliefs and appraisals in the maintenance and treatment of these disorders. He is a Fellow of the Canadian Psychology Association, was Founding President of the Canadian Association of Cognitive and Behavioural Therapies, and is a former Editor-in-Chief of the Journal of Behavior Therapy and Experimental Psychiatry. Dr. Radomsky trains therapists regularly both at Concordia and through lectures and workshops offered internationally.

Anna E. Coughtrey, DClinPsy, PhD, is a Clinical Psychologist and Senior Clinical Research Fellow at Great Ormond Street Hospital for Children NHS Foundation Trust in London, United Kingdom. She is widely known for her work in mental health research and her innovative projects. The Lucy Project, which provides accessible mental health support for children with long-term physical health conditions, was recognized with the Mental Health Team of the Year Award from The BMJ. Dr. Coughtrey's expertise includes obsessive–compulsive disorder, epilepsy, Long COVID, and COVID-19, and she has coauthored over 50 peer-reviewed articles.

Roz Shafran, PhD, is Emeritus Professor of Translational Psychology at the University College London Great Ormond Street Institute of Child Health in the United Kingdom. She is a Fellow of the Academy of Medical Sciences and of the British Association for Behavioural and Cognitive Psychotherapies. Dr. Shafran's formative years were spent with Jack Rachman at the University of British Columbia, Canada, where she saw firsthand the power of cognitive-behavioral therapy for obsessive–compulsive disorder (OCD). Her work has focused on the development, evaluation, and dissemination of treatments for perfectionism, OCD, and eating disorders, as well as mental health care for young people with chronic illness. Dr. Shafran has published over 400 research papers and has lectured and provided OCD workshops to clinicians globally. She is founder of the Charlie Waller Institute at the University of Reading and Patron of OCD-UK.

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