To achieve successful cooperative inter-firm relationships, trust between the partners is a key factor. As trust that is based on the self-commitment of the partners to behave in a non-opportunistic way (maxim-based trust) takes time to evolve and relies upon the cooperation experience of the partners, we expect that the positive performance impact of maxim-based trust grows over time. The purpose of this paper is to test the moderating effect of cooperation experience on the relationship between maxim-based trust and performance in the context of cooperating small and medium sized enterprises (SMEs) in two transformation economies (Czech Republic and Slovenia): Based on a sample of 124 SMEs, a moderated regression analysis reveals that trust and cooperation experience impact positively on performance. However, we could not detect a moderated relationship. We conclude that maxim-based trust may be an effective and efficent coordinating mechanism in the dynamic context of cooperating SMEs in transformation economies, but the absence of a moderating effect indicates that firms do not seem to increase the effects of maxim-based trust over time.