Do women have sex simply to express love, experience pleasure, or reproduce? When clinical psychologist Cindy M. Meston and evolutionary psychologist David M. Buss, both at the University of Texas at Austin, joined forces to investigate women's underlying sexual motivations, what they found astonished them.

Using women's own words, and backed by extensive scientific evidence, the authors delve into the use of sex as a defensive tactic against a mate's infidelity, a ploy to boost social status, a barter for household chores, and even as a cure for a migraine headache. Meston and Buss offer a revelatory examination of the deep-seated psychology and biology that often unwittingly drive women to have sex, sometimes in pursuit of joy, and sometimes for darker, more disturbing reasons.

Why Women Have Sex stands as the richest and deepest psychological understanding of women's sexuality yet achieved and promises to inform every woman's (and her partner's) awareness of her relationship to sex.