This innovative book introduces Group Radical Openness (GRO), a group treatment for individuals who struggle with costly and harmful overcontrol. The book opens with the background and evolution of GRO, followed by a thorough description of how to assess overcontrol. This novel group approach draws on both Group Therapy and Polyvagal Theory and encourages an entirely different way of working with this client group. It explores the concept of overcontrol, describing a pattern of distance in relationships, rigidity, and emotional inhibition. The 27-session group treatment leads the participants on a journey where they develop trust and safety with each other, show flexibility, and become more emotionally aware and expressive. Chapters feature engaging clinical examples and strikingly original exercises. This book is aimed at clinicians looking for ways to effectively treat disorders characterised by excessive self-control, such as mood disorders, eating disorders, and certain personality disorders. This will be an important resource in a wide range of mental health and forensic settings.