Despite increasing attention devoted to international entrepreneurship, little is known about firm-level entrepreneurship carried out by established small and medium-sized enterprises (SMEs) in international markets. We apply the opportunity-based conceptualization of “Entrepreneurial Management” by Howard Stevenson to international corporate entrepreneurship activities of SMEs. We hypothesize that the different dimensions of Stevenson's theory have a positive impact on SMEs' international corporate entrepreneurship. We test the hypotheses on a longitudinal sample of international SMEs. Our results show the expected positive effects of some, but not all, aspects of Stevenson's theory. Thereby, the paper suggests more precise boundary conditions of the theory and contributes to the literature on international corporate entrepreneurship by SMEs.