The article focuses on subcontractors’ capability of linking to local hubs of internationalized networks and using them as springboards to international markets. The aim of this paper is to analyze the causal relationships between subcontractors’ relational capabilities and their degree of internationalization, mediated by the level of the subcontractors’ involvement with local firms and networks linked to international markets. A multivariate causal model was tested through structural equation modelling on a sample of 104 Italian subcontracting small and medium enterprises (SMEs). The data suggest the positive role of local but internationalized supply networks in supporting subcontractors’ internationalization processes, while, surprisingly, we found that the linkage to localized multinational enterprises (MNEs) can have a negative influence on internationalization outcomes.