Complex trauma is the result of repeated or chronic traumatic experiences in childhood. The traumatic experiences have a pervasive impact on the child's physical, sensory, emotional, cognitive and social growth. This paper discusses how the proposed diagnostic category, Complex Trauma Disorder, identifies clusters of symptoms and behaviors that suggest the need for a multimodal approach to therapy. Application of each treatment modality is described with the emphasis on resolving the symptoms of complex trauma and development of a secure attachment.