Open Development (OD) is a subset of ICT4D that studies the potential of IT- enabled openness to support social change among poor or marginalized populations. Early OD work examined the potential of IT-enabled openness to decentralize power and enable public engagement by disintermediating knowledge production and dissemination. However, in practice, intermediaries have emerged to facilitate open data and related knowledge production activities in development processes. We identify five models of intermediation in OD work: decentralized, arterial, ecosystem, bridging, and communities of practice and examine the implications of each for stewardship of open processes. We conclude that studying OD through these five forms of intermediation is a productive way of understanding whether and how different patterns of knowledge stewardship influence development outcomes. We also offer suggestions for future research that can improve our understanding of how to sustain openness, facilitate public engagement, and ensure that intermediation contributes to open development.