In today's rapidly changing business landscape, entrepreneurship is growing and actively promoted by policy makers. Several reports explore the influence of entrepreneurship on the economy and put some emphasis on its positive influence GDP per capita, unemployment and exports. However, entrepreneurship does not go per se and it is now broadly admitted that the decision of the entrepreneur is narrowly connected with its environment, the so-called entrepreneurial ecosystem. This book show why policymakers, entrepreneurship supporters, and entrepreneurs themselves should keep in mind the locally structured nature of entrepreneurial networks. Even if the notion of Entrepreneurial Ecosystem has become quite popular, among the international organization, development agencies and public administrations, this concept is often considered as a new one having its origins in very recent publications. This books aims at showing that entrepreneurial ecosystems have their roots in the history of economic thought and that scholars have long been conscious of their importance. Instead of insisting upon the diversity of agents involved in these organizations, it also put some emphasis on the importance of the linkages and sharing between them and suggests some orientations in view of a performing evaluation system.