This article presents empirical research exploring adult students' transition to higher education (HE) through a program designed to enable that transition. Wenger's Communities of Practice theory has been applied to informal adult learning by Merriam, Courtenay, and Baumgartner (2003), who suggested its potential for understanding formal education. Using this theoretical framework, adults' transition to HE is explored in terms of learning, participation in practices, and identity. Students were interviewed, and qualitative data analysis revealed that although they perceived themselves to be peripheral participants in the community, university regulations, and academic procedures sometimes undermined their feelings of legitimacy. Their experiences of the community's practices were mediated by individual, shifting identities and a sense of belonging. Their experiences are discussed in terms of the power of practice to include or exclude, and the concomitant identity shifts which may lead to fuller participation. Implications for the design of transitional programs are also discussed.