A controversial figure, innovative scholar, and ardent advocate for sexual liberation, sexologist John Money opened a new field of research in sexual science and gave currency to medical ideas about human sexuality. This book offers, for the first time, a balanced and probing textual analysis of this pioneering scholar's writing to assess Money's profound impact on the debates and research on sexuality and gender that dominated the last half of the twentieth century. The author recovers Money's brilliance and insight from simplistic dismissals of his work due to his involvement in the tragic David Reimer case, while never losing sight of his foolhardiness.