A business cluster is a geographic concentration of interconnected businesses, suppliers, and associated institutions in a particular field. Clusters are considered to increase the productivity with which companies can compete, nationally and globally. They have the potential to affect competition in many ways: by increasing the productivity of the companies in the cluster, by driving innovation in the field, and by stimulating new businesses in the field.

It has been argued that economic activities are embedded in social activities and stronger inter-personal networks affect innovation to take place. Tallinn City Enterprise Department has taken a role as facilitator between local clusters. To support the international visibility, City of Tallinn has launched a joint portal for Estonian clusters /clustersinestonia to provide first-hand information about active clusters, their events and contacts for networking. In addition, informal meetings in form of Cluster Club will be organized once a month for the clusters to share ideas, find local partners, initiate joint projects and provide a platform for networking.