Based on Dr Fisher's groundbreaking personality type study, in which she analyzed the personalities of more than 28,000 match.com users, Why Him? Why Her? provides a formula for long-term love that is based on cutting-edge discoveries in evolutionary neurology.

Dr Helen Fisher is a research professor of anthropology at the University of Rutgers and one of the world's leading experts on the nature of romantic love and attachment. She would define herself as an Explorer.