This thesis examines the impact of the Lisbon Treaty on the rotating-presidencies ability to pursue national preferences and examines the consequences of these changes on the potential evolution of the EU as a whole. By using a qualitative text analysis and conducting a literature review this thesis acknowledges the subjective nature of a policy environment where almost all of the data and records of negotiation are kept behind closed doors. The literature review examines the theories and current thinking around leadership and negotiation with a particular emphasis on the European Union and the role of the rotating-Presidency. These theories examine the ability of the rotating-Presidency to act as a policy innovator through agenda- setting, prioritizing agendas and management of negotiations to elicit an outcome that is congruent with the national preferences of the Member State holding the office of the rotating-presidency. This thesis reviews the hypothesis that the Lisbon Treaty has removed the powers of the rotating-presidency by transferring agenda setting power to the elected-presidency and attempts to highlight trends in legislative outcomes that could explain a reduction in legislative vigour by the Council and the situation whereby a Member State’s ability to influence priorities or outcomes congruent with their national interests is contingent on the power and size of the Member State. The result of which could lead to a reduction in interest in the position of the rotating-presidency and the institutions of the EU by the Member States.