This chapter contains material relating to "the use of an object," a concept developed by Winnicott towards the end of his life. He made his main statement of it in a lecture given on 12 November 1968 to the New York Psychoanalytic Society: subsequently this appeared in the International Journal of Psycho-Analysis 50 (1969), and then in a slightly modified version in his posthumously published book Playing and Reality (1971). For the convenience of the reader this last version is reproduced here as Section I.