The ‘big bang enlargement’ of the European Union (EU) has nurtured vivid debates among both academics and practitioners about the consequences of ‘an ever larger Union’ for the EU’s integration capacity. The research project MAXCAP will start with a critical analysis of the effects of the 2004- 2007 enlargement on stability, democracy and prosperity of candidate countries, on the one hand, and the EU’s institutions, on the other. We will then investigate how the EU can maximize its integration capacity for current and future enlargements. Adopting an inter-disciplinary and mixed methods approach that combines desk research, in-depth interviews and Q-methodology, MAXCAP willa) explain the effects of the EU’s integration modes and strategies on democracy and socio-economic development in the new members, candidates and neighbourhood countries;b) inquire into the relationship between the widening and deepening of the EU by establishing conditions for effective decision-making and implementation in an enlarged EU;c) identify the social limits to the EU’s integration capacity related to citizens’ perceptions of the last and future enlargements;d) study the EU’s current and past negotiation strategies in the context of enlargement and investigate to what extent they need to be adjusted to changing conditions in the EU and the candidate countries;e) examine how the EU employs different modes of integrating countries with highly diverse economic powers, democratic qualities of governance, and institutional capacities andf) assess whether alternative models, such as the European Neighbourhood Policy, can be successful in bringing countries closer to the EU.MAXCAP which features a nine-partner consortium of academic, policy, dissemination and management excellence will create new and strengthen existing links within and between the academic and the policy world on matters relating to the current and future enlargement of the EU.