The interplay of foreign direct investment (FDI) with host locational characteristics has become an increasingly pertinent issue and this paper attempts to contribute to this proverbial 'black box' of research by profilling the host subnational location in a highly globalised economy. Building upon research on the activity of multinational enterprises (MNEs), this paper proposes that the subnational business system (SNBS) provides a novel theoretical framework upon which to explore FDI attraction and retention in the Republic of Ireland. Adopting this perspective, a profile of the subnational governance system and institutional network of actors in Ireland, particularly as it pertains to FDI, is illustrated through the lens of the SNBS. Sixteen key subnational institutional actors which have the potential to engage in the attraction and retention of FDI are identified and their role with MNEs categorised within the SNBS. From here, a potentially fruitful future research agenda is outlined which can deepen our understanding of the interaction between MNEs and institutional actors at the subnational level.