Market entry performance is critical during internationalisation; prevailing views suggest that firms need to carefully plan their entry before putting the plan into action. This article focuses on three attributes affecting the possibility and usefulness of making a pre-planned market entry: unpredictability, improvisation and business network commitment. We develop six hypotheses tested on a sample of 250 entries; our main finding is that improvisation plays a mediating role in relation to performance in unpredictable markets. The analysis reveals that the relationship between unpredictability and network commitment is not significant, while the effect of unpredictability on market entry performance is negative. These findings suggest implications for internationalisation and international entrepreneurship theory. For managers and entrepreneurs, we show that unpredictability weakens market entry performance, a negative effect that can be mitigated if the entrant firm improvises.