Freud’s model of the topography of the mind, first described in terms of the conscious-preconscious-unconscious and a simple conflict theory of the conscious opposing the unconscious. The more complex structural model of id, ego, and superego, and its correlated concept of intersystemic conflicts, replaced the topographic model, leading to a shift in clinical focus from discovery of unconscious drive-related wishes to a systematic analysis of the ego’s unconscious defensive operations.