Sigmund Freud (1856-1939) is best known as the Father of Psychoanalysis. An Austrian neurologist, Dr. Freud developed his theory of psychoanalysis in the 1890s as a way to treat his patients with symptoms of hysteria. He worked with Dr. Josef Breuer during that time in treating a female patient with a conversion disorder, with the use of psychoanalytic methods.

Although Freud’s theories have been controversial through the years, his pioneering work laid the foundation for modern psychology. Sigmund Freud was convinced that sexual conflicts and issues were related to most psychological problems. His work with the unconscious mind, the use of defense mechanisms, the sexual stages of development, and the different aspects of the psyche—the id, the ego, and the superego—were ground breaking and became the basic tenets of his psychoanalytic theory.