Complex trauma is based on underlying developmental trauma. However, developmental trauma is a very broad, non-specific category. There are several typologies and classification systems of developmental trauma available, with various degrees of usefulness to EMDR practitioners. Having researched and assessed these different theories, in this workshop I will offer an integrative synthesis relevant to EMDR practitioners. An understanding of the different types of developmental trauma can enhance our work both in terms of faster and more accurate diagnosis of developmental issues and also in eliciting relevant material and designing interventions. To establish key features of the client’s developmental issues, we can use a holistic spectrum of physical, affective and cognitive factors, including the client’s posture and body language, habitual cognitions and attitudes and modes of relating and expression. Most developmental theories share a common view of the key factors of developmental trauma: the child’s developmental stage, the intensity of the traumatising event, the available resources etc. But they vary greatly in terms of underlying meta-psychology and techniques and interventions.