- Simon Bulmer, Simon BulmerProfessor of Politics, University of Sheffield
- Owen Parker, Owen ParkerLecturer in European Politics, University of Sheffield
- Ian Bache, Ian BacheProfessor of Politics, University of Sheffield
- Stephen GeorgeStephen GeorgeEmeritus Professor of Politics, University of Sheffield
- and Charlotte BurnsCharlotte BurnsProfessor, University of Sheffield
This chapter examines a number of theories of European integration. It first considers the intellectual predecessors of the first attempts to theorize European integration, focusing in particular on the functionalism of David Mitrany, the federalism of Altiero Spinelli, and the ‘federal-functionalism’ of Jean Monnet. It discusses neofunctionalism and intergovernmentalism, along with liberal intergovernmentalism, and the fact that while theorizing European integration has moved on significantly from these early approaches, much of what followed was either framed by this debate or developed as a rejection of it. The chapter then introduces postfunctionalism as a more recent rival theory that helps explain the greater political controversy surrounding integration in the period following the Maastricht period, and particularly during the 2010s.