This article argues that to understand the use of evidence in policy, we need to examine how meanings and practices in the civil service shape what is accepted as knowledge, and how differences between the beliefs and values of the academy and the polity can impede the flow and transfer of knowledge. It considers the importance of social context and shared meanings in legitimating knowledge. Who counts as legitimate knowledge providers has expanded and here the role of stakeholder groups and experiential knowledge is of particular interest. How hierarchy, anonymity, and generalist knowledge within the civil service mediate the use of evidence in policy is examined. The difference in values and ideology of the civil service and the academy has implications for how academic research is interpreted and used to formulate policy and for its position in knowledge power struggles. There are particular issues about the social science nature of evidence to inform rural policy being mediated in a government department more used to dealing with natural science knowledge. This article is based on participant observation carried out in a UK Department of Agriculture and Rural Development.