We investigated the implicit psychological and behavioral consequences of sexual abuse in an adolescent girl who suffered child sexual abuse at preschool age in this case report. We report the manifestations of this abuse on her personality and psychological functioning using a structured clinical interview and a comprehensive psychological battery including the Beck Anxiety Inventory, the Beck Depression Inventory, the Standard Progressive Matrices, Rorschach Ink Blots, and the Schema Mode Inventory. These investigations were useful in formulating both a diagnosis and a management plan. The girl fulfilled diagnostic criteria for a major depressive episode and borderline personality disorder. This combination of psychological testing may be useful in establishing an accurate multiaxial diagnosis and for understanding the behavioral and psychological sequelae of child sexual abuse in similar cases. The study further suggests that schema-focused therapy is a useful therapeutic tool for individuals who have suffered child sexual abuse at an early age and who have borderline personality disorder.