The Evolution of Human Pair-Bonding, Friendship, and Sexual Attraction presents an evolutionary history of romantic love, male-female pair-bonding, same-sex friendship, and sexual attraction, drawing on sexuality research, gay and lesbian studies, history, literature, anthropology, and evolutionary science. Employing evolutionary theory as a framework, close same-sex friendship is examined as an adaptive trait that has harnessed love, affection, and sexual pleasure to navigate same-sex environments for both men and women, ultimately benefiting their reproductive success and promoting the inheritance of traits for friendship. Chapters consider the desire to form close same-sex friendships and ask if this is embedded in our biology, concluding that most humans have the capacity to form loving, meaningful, and sexual relationships with men and women. This book takes on a unique interdisciplinary approach and is essential reading for those studying and working in sexuality research, anthropology, sociology, evolutionary psychology, and gay and lesbian studies. It will also be of interest to marriage and family therapists as well as sex therapists.