Abstract: Transferring the leadership from parents to next generation is very common in family business. As the key issue of successor's willingness, family system was ignored in family business research. Based on the theory of family system, this paper uses the Qualitative Comparative Analysis (QCA) and fuzzy sets to analyze the data of twenty-two second generations from family firms, and proposes the SIF Model (Structure-Interaction-Function) to explore the multiple concurrent factors and causal complex mechanisms between the family and succession willingness. We conclude that the driving mechanism of high succession willingness can be classified into three paths: only-daughter succession, functional-governance,functional-communication. The first path refers to the match of the small-size family and the only daughter successor, and the other two paths show that how the functional family system matches formal governance and informal communication. Compared with functional-governance,functional-communication is more likely to nurture the next generation's willingness. Furthermore, in the family with more than one child, high-level communication leads to the high willingness of male successor. For those one-child families, maintaining good level of governance or only heiress may lead to high succession willingness. Finally, the driving mechanism of non-high succession willingness can be classified into two paths: dysfunctional-isolation, dysfunctional-conflict. There is an asymmetric relationship compared with the driving mechanism of high succession willingness.

Key words: family structure, succession willingness, configuration analysis, family system theory