This article presents an inventory and a typology of the existing and emerging economic clusters in the coastal zone of the European part of Russia. The authors hold that transboundary clustering takes priority in the Baltic coastal region — nine of the 56 clusters identified are located in the Kaliningrad region and another eight in Saint Petersburg and the Leningrad region. The authors describe major catalysts and immanent inhibitors in coastal zones. The former include a high density of coastal economies, proximity to international markets, and better logistics and communications. The inhibitors comprise geopolitical risks and institutional barriers. It is shown that the potential and prospects of transboundary clustering are affected by both global integration and disintegration patterns, coastal infrastructure, geopolitical and geoeconomic ‘neighbourhood’, cultural excellence, and business and investment environment.