While universities and other socially oriented organizations were among the first innovators in institutional ethical investing in the mid-twentieth century, university endowments are not represented among industry best practice in the impact investment sector. There is little systematic understanding of the values, decision-making processes, and management structures of such university funds or of how they relate to present-day initiatives of universities to render their endowments more responsible. Recent efforts to divest university endowments from fossil fuels exemplify the trend to focus on negative screening against harmful industries instead of on direct efforts to influence positive behavior through fund structure and destination. The last decade has seen the development of university foundations with explicit social responsibility mandates, but few of these initiatives use endowment funds or seek to engage the primary skillsets of universities: research, teaching, and local public engagement. This chapter focuses on the case of the University of Edinburgh's Social Investment Fund, established in 2017, to explore what might be specific about a university model of impact investment. It highlights three primary innovations within such a model: a whole-institution approach to social change; the use of new kinds of finance flows; and the deployment of a model of local collaboration to reduce risk, amplify benefits to investees, and contribute to local community development. This chapter suggests that a university model of social finance is not only a distinct model, but it is one that provides insights relevant to mainstream social finance and university sustainability agendas.