If the early years of the 21^st century could be marked as a ‘constitutional’ phase of European integration, then its aftermath can arguably be considered as a 'post-constitutional' phase of European integration. This nascent phase is marked by a series of crises both internal and external to the integration process. Internally, the ongoing saga of the attempts at constitutional reform culminating in the Irish ‘no’ to the Lisbon Treaty has been but the latest instalment of the EU’s uneasy relationship with referenda and popular sovereignty which stretches at least as far back as the ratification of the Maastricht Treaty. Externally, global economic meltdown and regulation of the financial and banking sectors - key aspects of the EU’s primary raison d’etre as a single market - poses questions about the liberalizing ethos which lies at the centre of the single market. In this workshop, these and other key issues will be analyzed in the interdisciplinary register of sovereignty. The question of crisis itself is intimately linked to the concept of sovereignty in the EU context in two main ways: On the one hand, the current crisis in integration can be interpreted as a resurgence of state sovereignty in the European constitutional configuration through inter alia the expression of popular sovereignty through referendums; whereas on the other hand the crisis can be interpreted as necessitating a further 'pooling' of sovereignty at the European level to cope with the external events affecting all Member States. These in turn potentially speak to a wider crisis of sovereignty itself in 21^st century Europe. Using insights from law and political science, various sovereignty-related aspects of the European integration process will form the perspective from which these questions will be addressed .