Women continue to remain in battering relationships because of financial dependency, emotional dependency, fear, lack of outside supports, victim-blaming, and immobilization resulting from shame and humiliation. Battering is cyclical and escalates over time. As the frequency and intensity of violent episodes increase, the victim develops a series of adaptations, termed battered woman's syndrome, that is characterized by feelings of isolation and powerlessness, extreme subservience and passivity, belief in the omnipotence of the batterer, hypervigilance, emotional disturbance, and physical symptoms. In cases where a plea of self-defense is entered, the expert witness is called upon to apprise the court of the defendant's state of mind and the dynamics of battering. In evaluating the defendant, medical records should be obtained, a history of the relationship and the abuse should be elicited, and the critical incident should be explored in detail. Close attention should be paid to the defendant's affect and level of fear. Psychological tests and interviews with others who knew of the abuse may aid in evaluations. During direct and cross-examination, the expert's demeanor should be professional. 28 references.