Beyond the categories of 'Alpha' world cities (with four sub-categories), 'Beta' world cities (three sub-categories), and 'Gamma' world cities (three sub-categories), the GaWC cities include additional cities at 'High sufficiency' and 'Sufficiency' level.

The GaWC inventory ranks city economics more heavily than political or cultural factors. The GaWC examines cities worldwide to narrow them down to a roster of world cities, then ranks these based on their connectivity through four 'advanced producer services': accountancy, advertising, banking/finance, and law. Smith, they create the GaWC's biennial categorization of world cities into 'Alpha', 'Beta' and 'Gamma' tiers, based upon their international connectedness. Together with Jon Beaverstock and Richard G.

It is based in the geography department of Loughborough University in Leicestershire, United Kingdom. The Globalization and World Cities Research Network ( GaWC) is a think tank that studies the relationships between world cities in the context of globalization.

Alpha ++ global city