The underlying premise in the creation of the ACC (predecessor of the CEB) was that an institutional mechanism was needed to draw the disparate parts of a decentralized system of specialized bodies - each with its own constitution, mandate, governing bodies and budgets - into a cohesive and functioning whole.
The UN Charter’s call for coordination through “consultation and recommendation” underscores the decentralized nature of the UN system. No central authority exists to compel compliance by organizations of the system to act in a concerted manner. Coordination and cooperation are contingent upon the willingness of system organizations to work together in pursuit of common goals.
In the many decades since its establishment there have been a number of reviews and reforms of the coordination machinery. In 2001, ACC was renamed the UN System Chief Executives Board for Coordination. CEB meets twice a year under the chairmanship of the UN Secretary-General.