Abstract
Background: The World Health Organization (WHO) ICD-11 now includes a distinction between the diagnoses of PTSD and complex PTSD (CPTSD). Several studies have indicated that this distinction is reliable and valid across various treatment services, communities and nations. An important next step is to determine to what extent this distinction will translate into clinical benefits. Investigations of treatment interventions and delivery strategies that have the potential to optimize outcomes for patients with ICD-11 PTSD and CPTSD while conserving clinical resources are needed.