"The occasion of the third millennium presents a timely opportunity for the only global organization, in terms of its membership as much as of its areas of work, to identify the challenges that it will face in the future and to engage in an imaginative exercise to enhance and strengthen a unique institution".

On 17 December 1998, the General Assembly of the United Nations adopted resolution 53/202 by which it decided to designate the fifty-fifth session the General Assembly to be opened on 5 September 2000 as "The Millennium Assembly of the United Nations" and to convene a "Millennium Summit of the United Nations". In endorsing the proposal for the Millennium Assembly and Millennium Summit, which has been put forward by the Secretary-General, the General Assembly decided that the turn of the century constitutes a unique and symbolically compelling moment for the membership of the United Nations to articulate and affirm an animating vision for the United Nations in the new era.

Heads of State and/or Government of the Member States of the United Nations gathered at the Headquarters of the United Nations in New York to participate in the Millennium Summit on 6 to 8 September 2000. The Summit was a historic opportunity to agree on a process for fundamental review of the role of, and challenges facing the United Nations in the new century.

On 3 April 2000, the Secretary-General presented his report "We the peoples: The role of the United Nations in the twenty-first century" (A/54/2000) in which he identified challenges facing the international community and put forward an action plan for addressing them.

In preparation for the Millennium Assembly and the Millennium report of the Secretary-General (A/54/2000), five informal regional hearings, organized in cooperation with the regional commissions of the United Nations, were been held in Beirut for Western Asia, in Addis Ababa for Africa, in Geneva for Europe, in Santiago de Chile for Latin America and the Caribbean, and in Tokyo for Asia and the Pacific, to elicit the views of civil society with respect to the Millennium Assembly.

As a companion event, and further to the Secretary-General’s recommendation, civil society organizations have organized and held on 22-26 May 2000 at United Nations Headquarters a "Millennium Forum" which has adopted the Millennium Forum Declaration and Agenda for Action.