This study attempts to develop our understanding of the entrepreneurial ecosystem as a complex social system. Using in-depth interviews, we model the entrepreneurial ecosystems of two municipalities through a diverse network of entrepreneurs, investors, institutional leaders and staff. The two ecosystems were characterized and compared on a set of measures related to the level of connectivity between actors, the existence of social boundaries, the role and position of actors with certain attributes (e.g. women, minorities) and the presence of ties in multiple social contexts (e.g. friend and investor). We found that social boundaries formed along venture type (e.g. high-growth/technology, lifestyle), type of support institution (e.g. university, government agency), gender, and ethnicity. High-growth/technology entrepreneurs, for example, were predominantly white, male and strongly connected to technology commercialization and acceleration programs. We also found that women and minorities are less embedded in the high-growth community than their male and ethnic counterparts.