Social and environmental accounting (SEA) is becoming commonplace in organisations that want to assess and report on their business ethics and sustainability performance. While there is an abundance of methods and standards that define how to perform such practice, tool support is much more limited and does not fully match the needs of organisations. In this paper, we present a model-driven engineering approach to support SEA. We are engineering a domain-specific language that allows creating models of SEA methods and we are implementing a tool that interprets such models at runtime, effectively supporting the accounting, and providing basic model management operations. This paper presents the preliminary results and, as a running example, we use UniSAF, a SEA method to assess the sustainability of universities. The results are promising, according to two SEA experts we have consulted, and have triggered the interest of the Fair Trade Software Foundation.