Clinical reports suggest that many adults who engage in self-destructive behavior have childhood histories of trauma and disrupted parental care. This study explored the relations between childhood trauma, disrupted attachment, and self-destruction, using both historical and prospective data. Seventy-four subjects with personality disorders or bipolar II disorder were followed for an average of 4 years and monitored for self-destructive behavior such as suicide attempts, self-injury, and eating disorders. These behaviors were then correlated with independently obtained self-reports of childhood trauma, disruptions of parental care, and dissociative phenomena. Histories of childhood sexual and physical abuse were highly significant predictors of self-cutting and suicide attempts. During follow-up, the subjects with the most severe histories of separation and neglect and those with past sexual abuse continued being self-destructive. The nature of the trauma and the subjects' age at the time of the trauma affected the character and the severity of the self-destructive behavior. Cutting was also specifically related to dissociation. Childhood trauma contributes to the initiation of self-destructive behavior, but lack of secure attachments helps maintain it. Patients who repetitively attempt suicide or engage in chronic self-cutting are prone to react to current stresses as a return of childhood trauma, neglect, and abandonment. Experiences related to interpersonal safety, anger, and emotional needs may precipitate dissociative episodes and self-destructive behavior.