Researchers and theorists who attempt to generalize about sexuality and sexual orientation in both men and women simultaneously often take male experiences as the norm and ignore unique aspects of women's lives. The purpose of this issue is to focus attention on scientific research and theory about aspects of women's sexualities, with special emphasis on sexual orientation. A new paradigm is presented that recognizes the great diversity of women's erotic experiences and the many sociocultural factors that shape women's sexuality and sexual orientation across the lifespan.