The historical analysis shows that - numerous difficulties and delays notwithstanding - “deepening” in the double sense of a rise in the scope and the level of European integration in the terms of institution-building, democratic legitimacy and European policies was the predominant trend in the history of European integration. “Widening” in the sense of a geographical spill-over never did prevent “deepening”. Rather it proved to be, even if at different degrees, a precondition for some steps of “deepening”. In order to substantiate this thesis this final state of the art paper of Team 2 will combine findings on the driving forces of European integration (I) and the resulting cycles in the development of the EU-system (II) with an analysis of the institutional logic of this development (III). As result, an assessment of the present situation will be presented (IV).