Generated the most controversy/exploation but lead to further thinking and development of therapy ---> building blocks.
Provided detail and comprehensive description of personality structure and functioning.
Focus on unconscious as a determinant factor of behavior and the role of trauma during the first 6 years of life
Led to the development of several techniques for tapping the unconscious and shed light on the dynamics of transference/countertransference, resistance, anxiety, and the mechanisms of the ego defense