This chapter provides the conceptual foundations for discussing the process and impact of co-creation as a mode of governance as developed in subsequent chapters. To do this, the chapter traces the genealogy of the notion of co-creation, discussing how it has become increasingly central to social science research, and defining the concept in ways that distinguish it from similar and related concepts such as corporatism and collaborative governance. Building on this genealogical approach, the chapter also discusses how recently developed theories may contribute to our understanding of the concept of co-creation and support its practical application. Finally, yet critically, the chapter will justify our attempt to elevate the concept from its original narrow focus on service production to a concept that aspires to become a new governance paradigm supplementing and partially supplanting Classical Public Administration and New Public Management.