The importance of high-growth entrepreneurship is widely acknowledged. Previous studies, however, have shown that only a few rapidly growing firms manage to sustain their growth trajectory over long periods. This paper addresses high-growth entrepreneurship in the Scania region of Sweden. The authors analyse a sample of high-growth firms and find that only a minority exhibit sustained high growth. They also compare sustainable high-growth firms with temporary high-growth firms, using unique data about their innovation and R&D activities. The analysis shows that sustainable high-growth firms are more often involved in activities aimed at developing and improving existing production processes, and are also less committed to international operations in new foreign markets. The results can be used to advise policy makers on how to understand and support high-growth entrepreneurship in regional innovation systems.