"Heterosexuality," assumed to denote a universal sexual and cultural norm, has been largely exempt from critical scrutiny. In this boldly original work, Jonathan Ned Katz challenges the common notion that the distinction between heterosexuality and homosexuality has been a timeless one. Building on the history of medical terminology, he reveals that as late as 1923 the term "heterosexuality" referred to a "morbid sexual passion" and that its current usage emerged to legitimate men and women having sex for pleasure. Drawing on the works of Sigmund Freud, James Baldwin, Betty Friedan, and Michel Foucault, "The Invention of Heterosexuality" considers the effects of heterosexuality's recently forged primacy on both scientific literature and popular culture.