This chapter traces the evolution of development cooperation within the United Nations across three interrelated dimensions: multilateralism and its reforms, the international development agenda, and financing for development. The construction of a common global agenda, shaped by the major summits of the 1990s, carried forward through the Millennium Development Goals (MDGs) and consolidated in the Sustainable Development Goals (SDGs), has represented a historic advance in development cooperation. However, the current diagnosis is complex: multilateralism is going through a crisis of confidence, implementation of the SDGs is lagging, and a substantial financial gap persists in achieving them. In response, the UN is driving ambitious and renewed approaches, including ongoing reforms, an agenda to accelerate progress towards the SDGs, and new proposals on financing, most notably the Fourth International Conference on Financing for Development held in Sevilla in 2025. These processes have renewed consensus and rebuilt confidence, reaffirming the value of multilateralism and the opportunity to reinvigorate international development cooperation.