Discussions concerning transsexual identities consider the self representations of transsexuals as either determined through medical discourses and practices, and thus as constructed and inauthentic or, alternatively, as expressive of an interior and thus ‘authentic’ essential self. In contrast to each of these arguments, this article highlights the significance of social interaction to transsexual authenticity and explores, specifically, how this can be analytically captured and presented in the context of interview-based research. The article applies analytic techniques drawn from fine-grain discourse analysis to research interviews carried out with female to male transsexuals. Through this method of analysis transsexual authenticity is treated as neither determined through medical discourses nor as interior to the self, but rather as a ‘live’ interactional accomplishment. By revealing the discursive identity work undertaken by the interviewees, the article demonstrates a constructionist approach to transsexual authenticity which, contrary to essentialist critiques, succeeds in foregrounding transsexuals as ‘constructing subjects’.