In this study we draw on the social network and international entrepreneurship literatures to examine the role of structural and relational embeddedness of international networks in firm internationalization. Based on a sample of 169 small‐ and medium‐sized enterprises in the Czech Republic, we found that firms with chief executive officers who had developed strong and diverse international networks exhibited greater knowledge of foreign markets prior to internationalization. However, contrary to our expectations, no relationship was found between network density and such knowledge. In addition, our findings indicate that foreign market knowledge prior to the first international venture had a positive impact on venture performance.