The adoption of the Agenda 2030 for Sustainable Development in 2015 marked the entry into a new promising era of international cooperation. It is also yet another milestone in the impressive history of the United Nations (UN). Since its establishment in 1945, the UN and its various agencies have been committed to engender global peace, stability and security, respect for human rights as well as multilateral cooperation. To date, there is little doubt that the UN have achieved many remarkable accomplishments in progressing towards these goals. However, the UN system is also facing growing scepticism. Critical voices point out its overburdening bureaucracy and inefficiency, questionable funding priorities and decision-making processes. Current trends in world politics also seem to undermine the idea of multilateral cooperation and the lack of commitment by member states is leading to a funding crisis for the UN agencies. With the current shifts in global politics, is the UN system at crossroads? How do we take stock of the achievements so far? What are the factors that may hinder the UN from reaching their full potential? Is the UN system still the best avenue to achieve peace and development globally? What reforms may be necessary to improve the system?