<p>The quality of entrepreneurial ecosystems not only enables local startups, but also affects the attraction and supply of non-local founders. We conceptualize entrepreneurial ecosystems as open systems with inflows and outflows of entrepreneurial talent. Beyond individual agency, these talent flows are driven by the quality of the origin and destination entrepreneurial ecosystems. We use network analysis and gravity models to study the interregional flows of founders of non-local startups within Italy and find empirical evidence for the creation, attraction, and supply mechanisms of entrepreneurial ecosystems. Entrepreneurial ecosystems not only provide a supportive environment for the creation of local startups, but also attract non-local founders. In addition, we reveal an escalator mechanism: (prospective) entrepreneurs tend to move from good to better entrepreneurial ecosystems.</p>