Neo-functionalism
In 1958, on the eve of the establishment of the EEC and Euratom, Ernst Haas published his seminal work, The Uniting of Europe, setting out a ‘neo-functionalist’ theory of regional integration. As elaborated in subsequent texts by Haas and other scholars (e. g. Haas 1961; Lindberg 1963; Lindberg and Scheingold 1970), neo-functionalism posited a process of ‘functional spill-over’, in which the initial decision by governments to place a certain sector, such as coal and steel, under the authority of central institutions creates pressures to extend the authority of the institutions into neighbouring areas of policy, such as currency exchange rates, taxation, and wages. Thus, neo-functionalists predicted, sectoral integration would produce the unintended and unforeseen consequence of promoting further integration in additional issue areas. George (1991) identifies a second strand of the spill-over process, which he calls ‘political’ spill-over, in which both supranational actors (such as the Commission) and subnational actors (interest groups or others within the member states) create additional pressures for further integration. At the subnational level, Haas suggested that interest groups operating in an integrated sector would have to interact with the international organization charged with the management of their sector. Over time, these groups would come to appreciate the benefits from integration, and would thereby transfer their demands, expectations, and even their loyalties from national governments to a new centre, thus becoming an important force for further integration.
At the supranational level, moreover, bodies such as the Commission would encourage such a transfer of loyalties, promoting European policies and brokering bargains among the member states so as to ‘upgrade the common interest’. As a result of such sectoral and political spill-over, neo-functionalists predicted, sectoral integration would become self-sustaining, leading to the creation of a new political entity with its centre in Brussels.