In 2005, a feminist educational organisation in the USA for young women, ages 14-21, adopted a policy in order to clarify their target constituency of girls and young women. The policy defined "girls and young women" not as a designation associated with fixed biological sex, but instead as a self-determined identity label creating an explicit policy of inclusion to gender non-conforming students, including transgender youth, who self-identified as "girls" or "young women". This article traces the series of influences that prompted the development of the policy, as well as the learning curves for this feminist educational all-girls' community, and the discussions that led to both the unanimous adoption of the policy and a subsequent larger cultural shift within the organisation. This analysis seeks to add to an understanding and exploration of policies that address the "de facto" exclusion of gender non-conforming, intersex, and transgender youth from gender-based educational settings. (Contains 1 table and 5 notes.)