WWACG

WWACG members play a key role in the air transport activities by assuring that aircraft operators flight intentions and among them airlines schedules meet the capacity requirements at the busiest airports worldwide and that the planning of the traffic on these airports is not generating built-in delays... Slots are allocated in accordance with guidelines set out in Worldwide Slot Guidelines (WSG). Airports throughout the world are categorised as either Level 1 (Non-Coordinated Airport), Level 2 (Schedules Facilitated Airport) and Level 3 (Coordinated Airport). Additionally, in some States or areas, such as in the European Union, legally binding regulations must be observed. They take then precedence. WWACG members and associate members execute their activities on the basis of the WSG, as well as national and local rules. About 320 airports worldwide are coordinated to (Level 3) or schedule facilitated (Level 2) standards.