Ruth Baer, PhD, is professor of clinical psychology at the University of Kentucky in Lexington, where she conducts research on mindfulness and teaches mindfulness-based treatments. She is the editor of two books: Mindfulness-Based Treatment Approaches and Assessing Mindfulness and Acceptance Processes in Clients.

Foreword author Mark Williams, PhD, is professor of clinical psychology at Oxford University, UK, where he is also Wellcome Principal Research Fellow. He is a Fellow of the Academy of Medical Sciences and a Fellow of the British Academy. He is author of many books and articles on the psychology of depression and its treatment, focusing on mindfulness-based approaches.