Entrepreneurial Ecosystems (EEs) are expected to support high growth entrepreneurship. Yet, little is known about how they actually promote entrepreneurial activities. Based on Giddens’ structuration theory, this paper takes the entrepreneurs’ perspective to understand how they actually use the resources provided by an EE. Based on semi-structured interviews with entrepreneurs and other relevant actors in the Berlin EE along with participant observation at entrepreneurship events, this case study focuses on the resourcing practices of different types of entrepreneurs. It shows that the Berlin EE comprises two distinct subsystems. On the basis of this evidence it is proposed that EEs can have different degrees of integration and that this characteristic strongly impacts how entrepreneurs can actually acquire resources from the EE and thus how specific EEs promote different types of entrepreneurs. Heterogeneous structures therefore do not only exist between EEs but also within EEs. This heterogeneity needs to be recognized in order to understand how EEs function, enhance the comparability of research results, and design suitable political instruments to promote entrepreneurship effectively.