Currently, there are no official treatment guidelines for complex posttraumatic stress disorder (cPTSD). The cPTSD differs from PTSD in the symptoms, duration or frequency of trauma exposure and in a high comorbidity with borderline personality disorder (BPD). Thus, there is a need for the development of new treatment methods targeted for this patient population. This article presents a new trauma-focused mentalization-based treatment using a group treatment approach that was developed for patients with cPTSD. In addition to the theoretical background and the conceptual framework of trauma in mentalization-based treatment, the treatment procedure is described in detail and illustrated based on a case example
