This article seeks to explore the relationship between the European Un
ion (EU) and the changing European order, with particular respect to t
he ways in which the EU structures and shapes the boundaries between i
tself and the broader European arena. It evaluates a range of availabl
e international relations theories, and adopts a 'critical neoliberal-
institutionalist' approach to the problem. It applies this approach by
assessing the EU's boundary-constructing and boundary-maintaining beh
aviour in a number of areas, before developing two models of the EU's
role: the 'politics of exclusion' and the 'politics of inclusion'. Aft
er spending most of its life practising the 'politics of exclusion', t
he EU has moved towards a 'politics of inclusion' to reflect the chang
ing demands of the European order. Nevertheless, the tensions between
the two types of politics will continue to be a central feature of the
EU's role.