A global city or world city is a concept promoted by the geography department at Loughborough University which postulates that globalisation can be broken down in terms of strategic geographic locales that see global processes being created, facilitated and enacted. The most complex of these entities is the "global city", whereby the linkages binding a city have a direct and tangible effect on global affairs through more than just socio-economic means, with influence in terms of culture, or politics. The terminology of "global city", as opposed to megacity, is thought to have been first coined by Saskia Sassen in reference to London, New York and Tokyo in her 1991 work The Global City.

General characteristics

• International, first-name familiarity; whereby a city is recognised without the need for a political subdivision. For example, although there are numerous cities and other political entities with the name Paris or variations on it, one would say "Paris", not "Paris, France".
• Active influence and participation in international events and world affairs; for example, New York City is home to the United Nations headquarters complex and consequently contains a vast majority of the permanent missions to the UN.
• A fairly large population (the centre of a metropolitan area with a population of at least one million, typically several million).
• A major international airport that serves as an established hub for several international airlines.
• An advanced transportation system that includes several freeways and/or a large mass transit network offering multiple modes of transportation (rapid transit, light rail, regional rail, ferry, or bus).
• In the West, several international cultures and communities (such as a Chinatown, a Little Italy, or other immigrant communities). In other parts of the world, cities which attract large foreign businesses and related expatriate communities; for example, Singapore, Shanghai, Hong Kong, Tokyo, and Moscow.
• International financial institutions, law firms, corporate headquarters, international conglomerates, and stock exchanges (for example the World Bank, or the London Stock Exchange) that have influence over the world economy.
• An advanced communications infrastructure on which modern trans-national corporations rely, such as fiberoptics, Wi-Fi networks, cellular phone services, and other high-speed lines of communications.
• World-renowned cultural institutions, such as museums and universities.
• A lively cultural scene, including film festivals, premieres, a thriving music or theatre scene (for example, West End theatre and Broadway); an orchestra, an opera company, art galleries, and street performers.
• Several powerful and influential media outlets with an international reach, such as the BBC, Reuters, The New York Times, or Agence France-Presse.
• A strong sporting community, including major sports facilities, home teams in major league sports, and the ability and historical experience to host international sporting events such as the Olympic Games, Football World Cup, or Grand Slam tennis events.

GaWC Inventory of World Cities, 1999