The essay traces the double, phenomenological and psychological, background of Sartre's theory of the imagination. Insofar as these two phenomenological and psychological currents are equally influential for Sartre's theory of the imagination, his intellectual project is situated in an inter-disciplinary research area which combines the descriptive analyses of Edmund Husserl with the clinical reports and psychological theories of Pierre Janet. While Husserl provides the foundation for the prevailing theory of imagination as pictorial representation, Janet's findings on obsessive behavior enrich an alternative current in Sartre's thinking about imagination as spontaneous and self-determined creativity.