In the 21st century, the United Nations is faced with a multi-layered reality of challenge and opportunity in international governance. Geopolitical competitions, non-state actors, rapid technological changes, and global environmental crises pose serious challenges to the United Nations' mandate for promoting peace, security, and sustainable development. But hidden in these challenges are opportunities for the United Nations to reassert its role as a dynamo of international cooperation and collective action. By initiatives such as peacekeeping operations in troubled regions, mediation and prevention of conflicts through diplomacy, and movements for sustainable development goals, the United Nations maintains its significant presence in addressing the challenges of a globalized world and advancing global interests. The qualitative research strategy, including document analysis and case studies, in this study attempts to analyze the UN's response to global issues and its evolving role in world governance. The findings present both success and failure in the UN strategy, offering insights on how to enhance its role in addressing new and future world challenges. Amidst the challenges of the 21st century, the United Nations remains a shining light in the promotion of peace, equality, and prosperity worldwide.

Keywords: United Nations, global governance, international cooperation, peacebuilding, development.