Entrepreneurial support organizations can play an important role in nascent entrepreneurial ecosystems by enabling productive and sustainable entrepreneurship. However, in such ecosystems, entrepreneurial support organizations may struggle to access the resources they need to activate their support. Drawing upon inductive qualitative research with 31 entrepreneurial support organizations and 40 interviews in Uganda, we examine how entrepreneurial support organizations navigate challenges of resource-constraints in nascent entrepreneurial ecosystems. A conceptual model is developed, depicting (1) key challenges entrepreneurial support organizations face in resource-constrained nascent entrepreneurial ecosystems, (2) the practices they enact to navigate such challenges, and (3) the implications of these practices at the meso-level of the “entrepreneurial support ecosystem.” We find that some entrepreneurial support organizations use adaptation practices to navigate challenges in nascent entrepreneurial ecosystems, while others deploy more agentic collaboration and transformation practices. We describe the latter as “ecosystem work” defined as efforts to create, maintain, and disrupt entrepreneurial support ecosystems. Finally, our model depicts how different navigating practices may influence entrepreneurial support dynamics. We suggest that while adaptation alone may result in stagnating entrepreneurial support ecosystems, “ecosystem work” may engender flourishing entrepreneurial support ecosystems.