Geoff Mulgan, a pioneer in the global field of social innovation - the deliberate invention of new solutions to meet social needs - explains how it provides answers to the most pressing global social, economic and sustainability problems. Building on his experience as a social entrepreneur, policy maker, funder and adviser to governments, businesses and foundations, he argues for matching research and development in technology and science with a socially focused research and development and for harnessing creative imagination on a larger scale than ever before.He shows how social innovation is now coming of age, offering a comprehensive view of what can be done to solve the global social challenges we face.