Management consultancy is a key sector in the economic change toward a service and knowledge economy. This book explains the mechanisms of the management consulting market and the management of consulting firms from both economic and sociological perspectives. It also examines the strategies, marketing approaches, knowledge management and human resource management techniques of consulting firms. After outlining the relationships between transaction cost economics, signaling theory, embeddedness theory and sociological neoinstitutionalism, Thomas Armbruster applies these theories to central questions such as: Why does the consulting sector exist and grow? Which institutions connect supply and demand? And which factors influence the relationship between clients and consultants? By applying both economic and sociological approaches, the book explains the general economic changes of the past thirty years and sharpens the relationship between the academic disciplines.