The recent financial crisis has once again seen John Kenneth Galbraith return to the bestseller lists. Yet, despite the continued popular success of his works, Galbraith's contribution to economic theory is rarely recognised by today's economists. This book redresses the balance by providing an introductory and sympathetic discussion of Galbraith's theoretical contributions, introducing the reader to his economics and his broader vision of the economic process. The book highlights and explains key features of Galbraith's economic thought, including his penetrating critique of society, his distinctive methodology, his specific brand of Keynesianism and his original - but largely ignored - contribution to the theory of the firm. It also presents, for the first time, a detailed examination of Galbraith's monetary economics and revisits his analysis of financial euphoria. This unique work seeks to rehabilitate Galbraith's contribution, setting out several directions for possible future research in the Galbraithian tradition.