Some processes used by female‐to‐male transsexuals in the formation of their sexual orientation identities were investigated under the assumption that for female‐to‐male transsexuals it is not possible simply to use their own sex or gender, or the sexual orientation identities of their partners, as bases for their own sexual orientation identities. Forty‐six North American and one New Zealand female‐to‐male transsexuals from diverse backgrounds and at different stages of transition were interviewed in depth about their sexual attractions, sexual practices, and sexual orientation identities as part of a larger sociological field study. For analytic purposes, hormone therapy was assumed to initiate sufficient changes in secondary sex characteristics to ensure that female‐to‐male transsexuals could function socially as men. Hormone therapy status was thus used to classify participants into pre‐and post‐transition groups. Prior to transition, female‐to‐male transsexuals tended to base their sexual orientation identities more on their gender identities and affectional preferences than on their sex identities, physical preferences, or sexual practices. After transition, female‐to‐male transsexuals who were sexually active were additionally able to make use of the sick role to base their sexual orientation identities on their sex identities. Forty percent of participants who were 10 or more years post‐transition reported having been sexually attracted to gay men. This may have been a reflection of their curiosity about the sexuality of men. I concluded with a theoretical model of the bases of sexual orientation identity which might be applied more broadly to other members of society.