 For many of his readers, the book on the Imaginary that Sartre published in 1940 constitutes one of the most rigorous and fruitful developments of his Husserl-inspired phenomenological investigations. Along with the The Emotions: Outline of a Theory which was published one year before (Sartre 1939b), Sartre presented this study of imagination as an essay in phenomenological psychology, which drew on his lifetime interest in psychological studies and brought to completion the research on imagination he had undertaken since the very beginning of his philosophical career. With this new essay, Sartre continues to explore the relationship between intentional consciousness and reality by focusing upon the specific case of the intentional relations to the unreal and the fictional, so as to produce an in-depth analysis of “the great ‘irrealizing’ function of consciousness”. Engaging in a detailed discussion with recent psychological research that Sartre juxtaposes with (and against) fine-grained phenomenological descriptions of the structures of imagination, his essay proposes his own theory of the imaginary as the corollary of a specific intentional attitude that orients consciousness towards the unreal.