Child abuse and neglect are universal risk factors for delinquency, violence and aggression; this phenomenon is known as the cycle of violence. Despite a wide body of research demonstrating this phenomenon, the processes which mediate this relationship remain largely unknown. One potentially relevant result of abuse and neglect may be disruptions in the development of the body’s stress response, specifically the function of the Hypothalamic-Pituitary-Adrenal (HPA) axis. The HPA-axis, and its end-product, cortisol, may play a role in regulating aggressive behavior, but this function may be disrupted following abuse and neglect. Another risk factor for aggression, psychopathy, may mediate the cycle of violence or independently contribute to aggressive behavior. This study examined the relationship between child abuse and neglect, HPA-axis function, psychopathy and aggression.