Drawing on the theory of social capital, we propose a cross-level model proposing that community-level social capital plays an important role in Open Source Software projects. Social capital, as resources lying within interpersonal relationships, is created and maintained as a by-product of social exchanges between developers working in the same OSS community. Social capital provides benefits both to the overall OSS community and to the individual developers. A high level of social capital in an OSS community can help facilitate the process of software development and make individuals’ experiences of working on OSS projects both satisfying and rewarding.