In this paper, a real clinical case is evaluated from a systemic point of view. María is an adolescent diagnosed with bulimia nervosa, who, initially, comes to the medical office to treat her eating disorder, but then she reveals that she has been a victim of intra-familial sexual abuse when the professional asks her about relationships between family members. This case will enable an examination of several matters: 1st. The importance of the frame of reference: the reality of the patient can be incomprehensible if the doctor only pays attention to the clinical situation, disregarding the ecology of her home environment. 2nd. The view of the disease as a symptom of inner suffering which has its origin in family difficulties. 3rd. The patient’s improvement begins with the disclosure of a traumatic secret, but not on the individual level, as in the classic psychodynamic model, but on a family level. 4th. The overcoming of the trauma, which was started with the revelation, is not completed until the readjustment of the family system.