In this paper I examine how young women construct their identities with others in online communities. I argue that the proliferation of social networking and its popularity among young people means that performed identities are increasingly collaboratively constructed, with the individual having less control over their public image than was previously the case. This has implications for how young women can understand themselves. In some ways this leads to an increased visibility and a blurring of public and private, frontstage and backstage arenas. It also, however, makes it possible for girls to gain support for alternative, more marginal, identities through interaction with online communities. I investigate the impact of these communities and the possibility that some may not be entirely benign. I also consider issues of authenticity and performance, and the impact of these on young women's understanding of and feelings about their bodies. Finally, I discuss possible pedagogic responses to these phenomena. (Contains 2 notes.)