Knowledge governance opens new pathways for collective action and is especially suited for solving complex societal problems. This paper analyses knowledge governance in two ways. First, it presents an overview of the literature on this topic with a particular focus on the principles of knowledge governance: self-organization, transdisciplinary knowledge production and dissemination, social learning, reflexivity and boundary management. Secondly, it presents the results of a case study to investigate the impact of, and the barriers to, knowledge governance. The case study is of the Dutch Northern Frisian Woodlands region, where a group of farmers, policy-makers, and scholars engaged in knowledge governance. We found that a limited ability and willingness of participants to commit themselves to the different principles was a major barrier to the functioning of knowledge governance. Furthermore, boundary management and the openness of organizations to learn about and change policies are crucial to gaining impact with knowledge governance.