This article examines the knowledge component in cluster literature from its origins to the present. A chronological perspective is deployed in order to shed light on how the concept of clusters has evolved. Given the increasing interest in clusters as knowledge repositories, and the apparent conviction among policy-makers of the manageability of clusters, lessons learned from knowledge management (KM) practices in organizations might well be applied to the many policy efforts aimed at governing clusters. We argue that introducing KM-initiatives on a regional level should be accompanied with an understanding of the possible downfalls that are associated with KM failures.