For almost thirty years the cluster concept and cluster policy have retained strong traction across both academic and policymaking circles. In this paper we select issues of current relevance, particularly for policymaking, from contexts of the evolution of understanding of the concept, the experience of implementing policy and ongoing research. The next section sets out key features of the cluster concept from its roots in Porter’s work (1990, 1998) and in well-worn considerations relating to agglomeration and innovation. Cluster policy experience is examined in the following section, in relation both to the Irish case and to international, mainly European, approaches and experience. For Ireland, a lack of an agreed, consistent or clear definition of cluster is revealed across policy documents and practice. The importance of amplifying connectivity between cluster members is considered fundamental to future cluster performance across regional and sectoral boundaries. This is increasingly important for innovation imperatives. The next section argues that to close the gap between government commitment to revising Irish cluster policy on the one hand and its implementation on the other, a number of issues must be addressed in terms of cluster policies, strategies and actions. Key to delivering impactful cluster policy are coordination and integration of approaches across relevant government departments and related agencies. In addition, we highlight a number of issues relevant for growing the evidence base on underlying structures and scales of relevance for an appropriately developed and targeted cluster policy for Ireland. These issues cover methods for identifying clusters, their relevant geographical scale and the applicability of cluster policy for different areas in Ireland. The final section sets out our concluding comments.