The inclusion of women in the U.S. military is generally understood as radically transforming traditional gender relations. Drawing from 38 interviews with women and men in the Reserve Officers' Training Corps, I ask: how do women negotiate gender identities within the "masculine" military institution, and what types of transformations in their gender ideology and practices does this negotiation entail? I find that ROTC women's transformative agency is limited by the cultural imperative of performing gender. That is, because their very identities as women are called into question in the military sphere, ROTC women must privilege traditionally feminine aspects of themselves in order to maintain a coherent sense of self. Through this process, these women ultimately reproduce traditional femininity and male privilege. (Contains 13 notes.)