Freud was an ambitious man and his communicative ability, both in speech and writing, made others interested in the psychoanalytic method. Freud, who was also a researcher, simultaneously developed a theory of how the psyche develops and works.

Freud's ambitious attitude, his desire to share his discoveries with others, and his interest in the surroundings resulted in the so-called Wednesday Club in 1902, where Freud and four interested parties, including Alfred Adler and Wilhelm Stekel, discussed Freud's theories.

By 1908 the company had grown to 14 people and in 1910 IPA was formed on the suggestion of Sandor Ferenczi. The first chairman was Carl Gustav Jung.