“Guanxi” is a term in Chinese referring to the reciprocal nature of interpersonal relationships. Its attributes, which are specific to Chinese culture, have been the focus of recent literature. Whereas the impact of guanxi seems to be quite similar to that of general relationships, ties or connections, it is characterized by a number of different dimensions. In this paper, we studied 44 entrepreneurial companies in the pharmaceutical industry in China to examine these attributes in greater detail. We use a system dynamics model to simulate the influence of various guanxi variables – the strength, scale and structure of guanxi – on the development of entrepreneurial companies.