This article concerns the recent shifts and tensions in the role of scientific knowledge in policymaking. Policy practitioners are striving to solve a compelling problem: how to deal with complex problems under conditions of uncertainty. This article focuses on two policy reforms in Finland that have been designed to address these issues: strategic governance reform and the take up of a culture of experimentation. It suggests that the knowledge-policy relations within these reforms are characterised by profound tensions between ‘good governance’ and ‘good knowledge’. Whereas good governance demands that knowledge is controlled, good knowledge entails uncertain and uncontrollable elements.