Homosexualities: A Study of Diversity Among Men and Women (1978) is a book by the psychologist Alan P. Bell and the sociologist Martin S. Weinberg in which the authors argue that homosexuality is not necessarily related to pathology and divide homosexuals into five types. Together with (1972), it is part of a series of books that culminated in the publication of Sexual Preference in 1981. The work was a publication of the Institute for Sex Research.