This chapter of Exploring Digital Libraries focuses on the potential of open access repositories for having a distinctive positive impact on scholarship and, more broadly, on their prospects for increasing the social and economic value of digital libraries. In addition to extending chapter 4’s discussion of open access repositories into new territory, it relates the frameworks presented in chapters 6 and 7 to this particular type of digital library. Topics include subject-based and institutional repositories and their value; issues around recruiting repository content, including deposit mandates; legal frameworks, copyright and open access; discipline-specific norms, practices and reward systems; the discoverability of scholarly content; sustainability of repositories; e-research data management; and prospects for the emergence of a global ecosystem of repositories.