Purpose: To consider the extent to which the legal recognition of non-binary gender has the potential to disrupt the gender binary. Methodology/Approach: This chapter will employ case study as method, focusing on recent changes to Australian law and policy, which introduce a third gender category. I rely on the work of queer theorists on normativity and recognition as a theoretical framework and on the work of social scientists on transgender people as evidence. Findings: This chapter finds that while there is much to be celebrated about increasing alternatives to the dominant categories of male and female, the legal recognition of non-binary gender may in fact serve to conceptually purge the dominant gender categories of non-conforming elements while simultaneously masking the ways in which institutions of regulatory power continue to demand conformity with normative standards of gender. Research Limitations: Since few non-binary individuals in Australia have adopted the X marker the implications laid out in this paper are speculative. The experiences of non-binary individuals present an important avenue for further research. Practical Implications: I recommend, as an alternative to further gender classifications, that we should seek to minimize the degree to which membership of a particular gender category is used to distribute rights and privileges. Originality/Value of Paper: This chapter advances the literature on nonbinary gender, contributes to existing queer and feminist analyses of the gender binary and extends work on normativity to legal recognition of alternative genders.