This chapter examines the concept of startup ecosystems as dynamic engines of innovation and economic growth by tracing the intellectual origins, conceptual evolution, and inherent limitations of the startup ecosystem approach. While the ecosystem metaphor has gained traction as a framework to analyse entrepreneurial environments, this chapter critiques its Western-centric foundations, which often overlook the distinctly different cultural, institutional, and historical forces shaping new venture formation in East Asia. We disentangle the ecosystem approach from related concepts like industrial districts, business clusters, and innovation systems, emphasising its focus on interactions between actors (entrepreneurs, investors, universities, and other supporters) and elements (such as cultural norms, local and international networks, material infrastructure, and government policy). We identify gaps in current conceptualisations and call for frameworks that bring to the fore contextual relevance. Ultimately, we argue that understanding East Asia’s ecosystems requires the reconciliation of global entrepreneurial trends with localised realities, offering foundational insights that underpin subsequent chapters on the entrepreneurial landscapes of Japan, Korea, and China.