The world is going through a reckoning. There is a gap between our perceptions and reality. We are moving back toward dysfunctional categories of the Cold War while postponing the real challenge, which is to define, design and implement multilateral cooperation. We witness the difficulty of finding sustainable solutions to the problems that afflict our common world on a daily basis. We witness insufficient commitments in cooperating effectively on global issues spanning ecology, disarmament of both conventional and nuclear arms, human rights, trade, pandemics, poverty and mass migration. In tandem with the resurgence of nationalism, this inaction is leading to the low tide of multilateralism. Multilateralism is not the property of any single organization. It is practiced in regional and subregional bodies, in development banks, in the trading system and its dispute settlement, in health and food security institutions, in climate and ocean regimes, in the technical and standard setting agencies that most citizens never hear of, in scientific cooperation, and in the daily work of missions and secretariats that rarely makes the news. Where it weakens, it weakens unevenly across these arenas, and the remedies are correspondingly different. A defense of multilateralism confined to a single headquarters would miss most of what is at stake. The retreat is felt first by those with the fewest alternatives. Official development assistance fell by 23% in 2025, the largest single year contraction on record, with the steepest reductions falling on the least developed countries and on sub-Saharan Africa. Core funding for multilateral organizations declined for a second consecutive year. Developing countries paid US $384 billion in interest on their external debt in 2024, and 3.4 billion people now live in countries that spend more on servicing debt than on health or on education. For these societies, international cooperation is not a preference of foreign policy. It is the difference between a clinic that opens and one that does not. All of this is compounded by a deficit of diplomacy, and a greater recourse to the militarization of political responses: a suboptimal, unsustainable, deadly and pervasive logic. The dialogue that underpins diversity is being supplanted by limited and stereotyped visions that are deeply anachronistic. As a meeting point, as a negotiation mechanism, and as the principal tool for strengthening lanes of communication on critical issues, dialogue loses force in the face of short range militarized responses. At the same time. the international governance system's decision making process remains centered around the nation state. To adequately address global challenges, it is necessary to involve non-state actors, subnational governments, the private sector, civil society and non-governmental organizations, among others, as well as the new social movements mobilized through networks. Let us not forget that the Charter of the United Nations begins with We the peoples. It is necessary to generate and foster a true culture of multilateralism. Civil society, academia, non-governmental organizations and the media should be part of a renewed constituency of multilateralism. That constituency will not appear on its own. It has to be built, and building it is work that can begin now. In this year in which we commemorate the 81st anniversary of the founding of the United Nations, we consider that the Pact for the Future, the Global Digital Compact and the Declaration on Future Generations, adopted by us all in 2024, constitute a roadmap for navigating the main challenges and conflicts of this twenty first century. Beside them stand the regional integration frameworks, the cooperation among developing countries, and the many functional regimes through which most cooperation is actually conducted. What is missing is not the diagnosis, and it is not, for the most part, the ideas. What is missing is the unification of our shared knowledge into proposals that institutions can take up today. This text is therefore not only a plea. It is an invitation to begin the work, and it opens with three fundamental questions. The first is the question of commitment. How can undertakings on which others depend be sustained through uncertain times, when a budget is revised, a mandate lapses or a majority changes, and when the consequences fall on societies that took no part in the decision? The debt burdens now carried across much of Africa are one case among several in which cooperation is least reliable exactly where it is most needed. The second is the question of means and of participation. How can institutions be given resources they are able to count on, and how can actors who are not states be party to decisions that concern them in a manner that is regular and continuous rather than occasional? The third is the question of the division of labour. On what terms should regional and global institutions defer to one another, and how should responsibility be allocated when mandates overlap, priorities diverge, and capacities differ? Who will act first, who can support, and how will shared objectives transpose into shared outcomes? Each question will be the subject of a cycle of discussion, the first in Paris and others across the globe, and each will conclude in a published report setting out an argued and quantified list of proposals. To the academic community. We invite universities, research centers and individual scholars to submit proposals addressed to one of these three questions. The subject belongs to no single discipline. It is a matter for international relations and international law, and equally for economics, political science, sociology, anthropology and history. Our purpose is to gather the current state of the art of the social sciences on the conditions of cooperation, and to render it usable for those at the forefront of its negotiation. To officials, diplomats and groups of states. We invite you to accompany, to host and to sponsor this work. To open a session, to send a speaker, to lend the standing of an institution to a deliberation whose conclusions remain those of their authors. Complete agreement with any particular proposal is not the goal, and nothing here commits a government to a position. To all who share this concern. Sign and bring others to do so as well. A constituency is counted before it is heard. To sign this text is to support the search for solutions. It is not to endorse in advance the solutions that will be found. The reports will be sent to every signatory, and each will remain free to associate with them or not. From the close of the first cycle, the proposals will be carried to the international and regional organizations they concern. The three reports together will be presented at the General Assembly in 2028. This roadmap must be approached with a humanistic vision, in which human flourishing is placed at the center and is the core purpose of any sustainable solution.