In 1955, the controversial and innovative sexologist John Money first used the term “gender” in a way that we all now take for granted: to describe a human characteristic. Money’s work broke new ground and gave currency to medical ideas about human sexuality. As an ardent advocate for sexual liberation, he became something of a fixture in the popular imagination. This book cuts through Money’s talent for polemic and self-promotion by digging into the substance of Money’s theories and achievements. It 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. Through his analysis, Goldie 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 flaws.