The social economy is rapidly gaining in visibility at the international, national and local levels in most OECD member countries. Social economy -- also know as 'non-profit' or 'third sector' -- organisations have grown in number and relevance, contributing to employment, social inclusion, democratic participation and community building. Much remains to be done, however, to create the necessary enabling environment to support the creation and development of social economy organisations and to mainstream the sector in economic and social policies in order to maximise its impact on the economy. This publication offers new insights into the economic theory of social economy organisations, their role in an evolving political and economic context, and the links to local development and the empowerment of users. Building on theoretical and empirical developments in OECD member countries, the publication also presents the main challenges for the social economy in Central East and South East Europe. Recommendations for action are included. The book is essential reading for policy-makers, practitioners and scholars interested in the latest theoretical and empirical developments in the field of social economy in OECD member and non-member countries.