This article explores the role of firm-level human capital for the internationalization of small and medium-sized enterprises (SMEs). Building on the resource-based view of the firm and theories of SME internationalization, we hypothesize that the level of human capital will vary with SME internationalization strategy and will be of considerable importance for firms that follow a strategy of accelerated internationalization. At the same time, we suggest a threshold point, after which additional firm endowments of human capital become less productive. We test our ideas using a unique dataset of all manufacturing SMEs in Belgium which internationalized between 1998 and 2005. Findings indicate a significant curvilinear (inverted U) association between the level of human capital and the firm’s export intensity when firms choose a strategy of accelerated internationalization.