Most cities, though not all, are much older than the countries in which they are located. There has been a continuity of human endeavour in London, Rome and New York that pre-dates the existence of the United Kingdom and England, Italy and the United States. That will doubtless continue. Most great cities have become great cities not because they have been created as administrative centres (pace Brasilia, Washington DC and Canberra) but rather because they have long served fundamental human economic needs.

We now live in a more global economy than at any previous stage in the history of our species. It is also, thanks to this phenomenon we call globalisation, rapidly becoming a more balanced one, with the huge populations of China and India at last starting to exert their economic might alongside Europe and North America. This is arguably the most important shift of power and wealth since the Industrial Revolution, certainly the most important since the shift of economic power from Europe to the US during the past century. Yet, one of the most astounding aspects of this transformation is that it is taking place without any central direction, any plan, or indeed any single centre from which it is being choreographed. There is no capital of the world economy, rather a set of places that derive their importance by providing services to it.

The quest that my colleagues on the travel desk set out upon when trying to rank global cities was not just to create a league table though that has proved both fun and illuminating but more to explore what is happening to the world. The exact choice of criteria is, to some extent, arbitrary but high up the pecking order must be what is happening to travel. Globalisation is not just about moving money, goods and services around. It is also about moving people and ideas around. When we travel we move our bodies but we also move our minds. (That is why Unesco World Heritage Sites and symphony orchestras feature.)

So what The Independent Traveller has created here is not so much a league table as, by looking at cities, an exploration of globalisation itself. There are a tiny handful of places that have a claim to being truly global, in the sense that they are big, culturally diverse and generate a set of services and ideas that are helping shape the ever more global economy. For those of us who are based in London, the objective supremacy of this city, given its scale and diversity, comes as no surprise. The battle between London and New York either end of the world's busiest intercontinental air route has been widely publicised, and it is fascinating to see that today's ranking squares with other assessments of the relative significance of these two cities.

But of course there are global centres of particular activities that matter hugely too: Los Angeles and Mumbai in entertainment, Barcelona and Berlin for nightlife, and so on. There are also strong regional centres that are powerful but not yet particularly diversified: Moscow, Seoul and perhaps Shanghai. There are places that punch above their weight: Sydney, nudging prime global status, and at a different level, Madrid, Amsterdam, Singapore. There are also many places that punch below, that are not as important to the world as they ought to be given their scale and energy. I would cite Sao Paulo, Cairo and Bangkok. There are shooting stars: Dubai is the most remarkable. And there are some cities that we have not covered, yet are important to their regions: I would like to see what happens to Guangzhou (formerly Canton), Tehran and Jakarta over the next generation.

This is a journey, though, on which it is better to travel than to arrive. What is happening to the world economy is so huge and we need to recognise that there are costs as well as benefits that any city that can make a positive contribution to globalisation deserves a fair wind. It will be global cities, rather than national governments, that will shape the world economy over the next generation. So let's hope they manage to do so for the better.

Meanwhile, welcome to a world where cities once again count for more than countries.

Missing Metropolises: The cities that got away

Many more cities were considered but failed to make the cut for the final 60. Although Kingston and Port of Spain are the capitals of, respectively, Jamaica and Trinidad, neither comes close to Havana as capital of the Caribbean; similarly, Suva, Papeete and Honolulu trailed behind Auckland (right) as capital of the Pacific. Because this survey has been compiled by the travel desk, there is an unabashed interest in each city as a tourist destination; great cities of the Islamic world, such as Karachi, Tehran and Jakarta, are not been included. Next year, we shall expand the selection. Vienna, Prague and Budapest comprise a missing middle-European troika, while Panama City and Bogota can make strong claims for Latin America. We may also start subtracting points for the number of times a city has staged that cultural aberration, the Eurovision Song Contest watch out, Dublin (six times).