In recent years scientific research and popular opinion have favored the idea that sexual orientations are determined at birth. In this book, philosopher and legal theorist Edward Stein investigates scientific research on sexual orientation and shows that it is deeply flawed. He argues that this research assumes a picture of sexual desire that reflects unquestioned cultural stereotypes rather than cross-cultural scientific facts, and that it suffers from serious methodological problems. He then asks whether sexual orientation is amenable to empirical study and if it is useful for our understanding of human nature to categorize people based on their sexual desires. Perhaps most importantly, Stein examines some of the ethical issues surrounding such research, including gay and lesbian civil rights and the implications of parents trying to select or change the sexual orientation of their children.