This book provides an exhaustive, critical analysis of the challenges and opportunities associated with social enterprises and social innovation. More specifically, it addresses questions such as: What is a social innovation? Which are the best theories that explain how social innovations are generated and propagated in the global society? What is a social enterprise? Which are the theoretical perspectives that best describe the functioning of Social Enterprises , the threats and opportunities? How do social enterprises deal with the profit and non profit worlds and how these interactions affect their capability to be social innovators?The most recent literature has focused on strategies integrating conflicting logic, organizational practices or processes. In all these cases, the hybrid nature of the organization is implemented and sustained through original business models, new organizational arrangements and governance and novel strategies. We believe that the hybrid and institutional perspectives are just one of the many theoretical lenses that can be used to frame social innovation and social enterprises. Along this line, some have highlighted the inherent ethical nature of these phenomena, the critical role played by ethical values whose advancement go well beyond what expected by the corporate social responsibility, business ethics and institutional theorizing.