The paper explores the relational organization of entrepreneurial ecosystems, arguing that they are composed of ten cultural, social, and material attributes that provide benefits and resources to entrepreneurs. These attributes interact to create and reproduce the ecosystem, which is not defined by high rates of entrepreneurship but by how these attributes interact to create a supportive environment for new ventures. The paper uses case studies of Waterloo, Ontario and Calgary, Alberta, Canada to illustrate the different configurations of entrepreneurial ecosystems and how they affect the types of resources entrepreneurs can access. Waterloo's ecosystem is driven by a strong entrepreneurial culture that fosters networks of entrepreneurs, advisors, and investors, along with well-performing public entrepreneurship programs. This culture supports a high-risk, high-growth entrepreneurial environment. In contrast, Calgary's ecosystem is dominated by the oil and gas sector, which provides numerous opportunities for new ventures and attracts skilled workers and financial capital. However, the cultural and social attributes in Calgary are weaker, leading to less effective entrepreneurial networks and support systems. The paper identifies ten core attributes of entrepreneurial ecosystems: cultural, social, and material. These include cultural attitudes and histories of entrepreneurship, social networks, investment capital, mentors and dealmakers, and worker talent. Material attributes include universities, support services and facilities, policy and governance, and open markets. These attributes interact to create a supportive environment for new ventures. The paper argues that successful ecosystems are not defined by high rates of entrepreneurship but by how the interaction between these attributes creates a supportive environment that increases the competitiveness of new ventures. The case studies of Waterloo and Calgary illustrate the different possible configurations of entrepreneurial ecosystems and how these configurations affect the entrepreneurship process. The paper concludes that entrepreneurial ecosystems are complex and multifaceted, with multiple ways they can develop. Understanding the relational organization of entrepreneurial ecosystems is essential for policymakers and entrepreneurs to create and sustain successful ecosystems.The paper explores the relational organization of entrepreneurial ecosystems, arguing that they are composed of ten cultural, social, and material attributes that provide benefits and resources to entrepreneurs. These attributes interact to create and reproduce the ecosystem, which is not defined by high rates of entrepreneurship but by how these attributes interact to create a supportive environment for new ventures. The paper uses case studies of Waterloo, Ontario and Calgary, Alberta, Canada to illustrate the different configurations of entrepreneurial ecosystems and how they affect the types of resources entrepreneurs can access. Waterloo's ecosystem is driven by a strong entrepreneurial culture that fosters networks of entrepreneurs, advisors, and investors, along with well-performing public entrepreneurship programs. This culture supports a high-risk, high-growth entrepreneurial environment. In contrast, Calgary's ecosystem is dominated by the oil and gas sector, which provides numerous opportunities for new ventures and attracts skilled workers and financial capital. However, the cultural and social attributes in Calgary are weaker, leading to less effective entrepreneurial networks and support systems. The paper identifies ten core attributes of entrepreneurial ecosystems: cultural, social, and material. These include cultural attitudes and histories of entrepreneurship, social networks, investment capital, mentors and dealmakers, and worker talent. Material attributes include universities, support services and facilities, policy and governance, and open markets. These attributes interact to create a supportive environment for new ventures. The paper argues that successful ecosystems are not defined by high rates of entrepreneurship but by how the interaction between these attributes creates a supportive environment that increases the competitiveness of new ventures. The case studies of Waterloo and Calgary illustrate the different possible configurations of entrepreneurial ecosystems and how these configurations affect the entrepreneurship process. The paper concludes that entrepreneurial ecosystems are complex and multifaceted, with multiple ways they can develop. Understanding the relational organization of entrepreneurial ecosystems is essential for policymakers and entrepreneurs to create and sustain successful ecosystems.