The article considers how twins discursively negotiated and performed their twinship over the twentieth century through an examination of the jointly written narratives of self of three sets of identical, female, American twins. These years witnessed a shift in the academic, medical, and lay attitudes toward twins—a historical and social shift that I argue is reflected in their narratives and in their perceptions of self. Taken together these three joint autobiographies suggest that researchers’ findings regarding the movement of twins along a scale from compliance to contestation to denial is also a temporal movement, reflecting a gradual shift in social and gender expectations regarding twinship. The article sheds light on the history of the lived experience of twinship, in particular that of female twins, and reflects on a more general historical evolution of twentieth-century women’s performance of their individuality. After an introduction to the six women and their narratives of self, I turn to outline how each set of twins presented their twinship and individuality in their narrative. I conclude by considering some aspects concerning the historicity and gendering of twinship.