This paper applies the SIAMPI approach, which focuses on the concept of productive interactions, to the identification of the social impact of research in the social sciences. An extensive interview programme with researchers in a Welsh university research centre was conducted to identify the productive interactions and the perceived social impacts. The paper argues that an understanding of and focus on the processes of interaction between researchers and stakeholders provides an effective way to study social impact and to deal with the attribution problem common to the evaluation of the social impact of research. The SIAMPI approach thereby differentiates itself from other forms of impact assessment and evaluation methods. This approach is particularly well-suited to the social sciences, where research is typically only one component of complex social and political processes. Copyright , Beech Tree Publishing.