Crowdsourcing is a relatively recent phenomenon that only appeared in 2006, but it continues to grow and diversify (crowdfunding, crowdcontrol, etc.). This book aims to review this concept and show how it leads to the creation of value and new business opportunities. Chapter 1 is based on four examples: the online-banking sector, an informative television channel, the postal sector and the higher education sector. It shows that in the current context, for a company facing challenges, the crowd remains an untapped resource. The next chapter presents crowdsourcing as a new form of externalization and offers definitions of crowdsourcing. In Chapter 3, the authors attempt to explain how a company can create value by means of a crowdsourcing operation. To do this, authors use a model linking types of value, types of crowd, and the means by which these crowds are accessed. Chapter 4 examines in detail various forms that crowdsourcing may take, by presenting and discussing ten types of crowdsourcing operation. In Chapter 5, the authors imagine and explore the ways in which the dark side of crowdsourcing might be manifested and Chapter 6 offers some insight into the future of crowdsourcing. Contents 1. A Turbulent and Paradoxical Environment. 2. Crowdsourcing: A New Form of Externalization. 3. Crowdsourcing and Value Creation. 4. Forms of Crowdsourcing. 5. The Dangers of Crowdsourcing. 6. The Future of Crowdsourcing. About the Authors Jean-Fabrice Lebraty is Professor of management sciences at IAE (Business School) at Jean Moulin - Lyon 3 University in France and a member of the research laboratory Magellan EA3713. He specializes in the management of information and communication systems and his research notably concerns decision-making and the links between crowd and information technology. Katia Lobre-Lebraty is Associate Professor of management sciences at IAE (Business School) at Jean Moulin - Lyon 3 University in France and a member of the research laboratory Magellan EA3713. She specializes in management control and strategic management and her research concerns both the modes of governance of organizations and Open Data