Evidence indicates that childhood sexual abuse is a major risk factor in the development of depression, borderline personality disorder, substance abuse, and dissociative disorders. Research also shows that childhood trauma can have profound effects on adult psychophysiology and that some disorders exhibit psychobiological effects of trauma more than others. The trauma model of psychopathology predicts that severe childhood trauma causes a longlasting dysregulation at all levels of the organism. In particular, this model predicts that, in some families, depression is driven primarily by trauma. Treatment needs for these families are determined more by trauma history than by the mix of concurrent diagnoses. 10 references