This Modern Guide presents a comprehensive synthesis of contemporary knowledge on the social and solidarity economy (SSE). It provides an overview of the conceptual, historical, organizational, and developmental dimensions of the SSE, exploring current issues through the lenses of public policy, governance, finance, and legislation. Highlighting the SSE’s transformative ability to mobilize communities and connect North–South social debates, expert contributors analyse current arguments spanning tensions in hybrid organizations, internationalization, and networks and ecosystems governance. Chapters combine theoretical perspectives with empirical examples, presenting unique insights into researching, developing, and participating in the SSE. Expert authors argue that the SSE can foster equitable patterns of resource and surplus distribution, and promote democratic, capable, and emancipatory power relations. They examine SSE enterprises including cooperatives, mutual societies, non-profit organizations, and community-based initiatives that place social and environmental missions above profit generation, proposing compelling avenues for future research. This book is a fundamental resource for scholars and students in economics and finance, business and management, and social policy. SSE actors and policymakers, particularly those involved in sustainable development, public services, and local development, will also benefit from its valuable discussions.