In this essay, I explore empirical research about the relationship between sexual orientation and gender. Both concepts have multiple meanings, which hinder an unequivocal understanding of the relationship between the two concepts. One of the first studies assumed to establish a relationship between male homosexuality and femininity was conducted by L. M. Terman and C. C. Miles (1936). The study actually gives a much more complicated picture of the relationship. Terman and Miles actually found two groups of homosexual men with, respectively, extremely high masculinity and extremely high femininity scores. Subsequently, various other studies examined the relationship between sexual orientation and gender, introducing the concept of androgyNY. While these studies were executed, major changes took place in the homosexual world, which have been characterized as the masculinization of culture. It is unclear how these changes relate to the masculine and feminine properties of the men involved. Various suggestions are made for further research on the relation between gender and sexual orientation.