Sustainable entrepreneurial ecosystems (SEEs) have become increasingly vital in addressing global sustainability challenges while fostering economic innovation. This chapter provides a conceptual exploration of SEEs, which integrate environmental stewardship, social equity, and economic viability into entrepreneurial systems. Drawing on theoretical frameworks including the Triple Bottom Line approach, stakeholder theory, and social capital theory, we explain how sustainable entrepreneurial ecosystems (SEEs) differ from traditional entrepreneurial ecosystems in their emphasis on long-term resilience and sustainability-oriented innovation. The discussion highlights key components of SEEs—such as institutional support mechanisms, financing structures, and collaborative networks—while identifying persistent challenges in their development. By synthesizing current research, this descriptive chapter offers a foundation for understanding how SEEs can align business innovation with sustainable development goals, providing insights for scholars and practitioners in the field.