Ordoliberalism is often recognized as a powerful ideational source during the Euro crisis; however, there is no pure ordoliberal vision of European integration, and ordoliberal ideas have been used to support both Eurosceptical and Europeanist positions during the crisis. This article reconstructs the ordoliberal theoretical and political debate on European integration and argues that there exist two ordoliberal paradigms of European integration: one bottom-up, whereby the commitment to liberal economic policies at the national level is the precondition for a liberal (...) international order; the other top-down, whereby a liberal international order can help the establishment of a liberal order at the national level. The article compares two ordoliberal visions of the international order: Wilhelm Röpke’s ‘liberalism from below’ (which follows the bottom-up logic) and Viktor Vanberg’s ‘competitive federalism’ (which follows the top-down logic). Then, it explores the ordoliberal political debate on two episodes of the European integration process – the Maastricht Treaty and the Euro crisis – to argue that the bottom-up and the top-down logics underpinned, respectively, Eurosceptical and Europeanist arguments. (shrink)