The 2005 World Summit was announced as a once-in-a-generation opportunity to reform the United Nations so as to provide it with the institutional and policy tools needed to meet the challenges and threats to peace and security in contemporary world. But the Summit was also meant to be a crucial test for the EU common foreign policy and for the state of transatlantic relations. As a matter of fact the success of any UN Reform could be hardly envisaged without the capacity of EU Member States to advance common and consensus-gathering positions andwithout bridging the gap between US and EU strategic visions on multilateralism and global governance. In order to discuss whether in New York an historic occasion has been seized or rather lost, a group of distinguished scholars and high level diplomats was convened in Florence at the joint invitation of IAI, EUI and UNICRI in the aftermath of the World Summit. This Working Paper reports the debate held at the international conference and offers a first assessment of the main outcomes of the Summit while drawing the future perspectives of the UN reform process. It is submitted that the Summit has fallen short of the historical UN reform the Secretary General had hoped for, but nonetheless it records some positive advancements. This is especially the case of those issues where a transatlantic agreement was reached, such as the decision to establish a Peace Building Commission for post-conflict reconstruction, the establishment of a Human Right Council and of a Democracy Fund to strengthen the countries’ capacity to implement the principles of democracy and the express endorsement of the newguiding concept of responsibility to protect the victims of severe violations of human rights.In other fields, achievements have to be measured against the ambiguity of the final text and room is left to further negotiations. For instance, the key concept of human security, which have been launched in the Report of the High Level Panel’s on Threats, Challenges and Changes (A More Secure World: Our Shared Responsibility), is endorsed but watered down to some very generic statement and a clear commitment to discuss further the notion in the General Assembly. Similarly, the historic decision to set up a new Human Right Council fails in addressing all the relevant features of the new organ (compositions, status, powers and relationship with existing organs and procedures) which are left to further negotiations in the General Assembly. A final evaluation remains therefore controversial. Lack of progress has to be recorded in core policy areas. In the field of development and environment the outcome document simply restates principles and commitments already affirmed. In the field of peace and security, no significant progresses were made in providing a global framework to combat terrorism nor specific commitments on disarmament and non-proliferation were assumed. In the highly-politicised issue of Security Council Reform, the division among EU member states did not help to reach a compromise solution. However, as a test for the EU capacity to act jointly and effectively on the international level, the World Summit has yielded positive results. The EU member States succeeded in putting their political weight behind a proactive attitude throughout the process, in pursuit of a number of clear objectives. On many issues, Europe may take the lead of the reform process, building on its own experience in promoting a lasting peace, protecting human rights and fostering development. Its commitment to an effective multilateralism attempts to promote a successful global governance without yielding to the temptation of unilateral drifts. No matter how determined and powerful, a single State or group of virtuous States cannot face the threats and challenges of a global world alone. In its endless opposition to unilateralism, multilateralism is mandated by the need for an effective global governance. For many, respect – and maybe with the exception of the field of global economic governance – the UN remains a viable and irreplaceable institution. In this regard, the foremost achievement of the World Summit is precisely the fact that all the members of the UN have restated the central role of the Organization in providing global governance and have committed themselves to strengthening its effectiveness.