A.T. Kearney's survey measures business activity, human capital, information exchange, culture and political engagement. These factors naturally favour big cities, so the dominance of melting-pot metropolises isn't surprising. The lead of the top few over the rest suggests the Big Apple, London and the rest won't be dethroned quickly.

But in a decade or two, the survey reckons, cities that are now emerging could reach the top of the list. Chief among these are Beijing and Shanghai, where rising wealth, expanding infrastructure and improving business conditions may well outweigh negatives like pollution and the political environment.

Mercer's report on the quality of life offers a different view of the future. A good lifestyle doesn't match with global prominence. None of Mercer's top five cities features in A.T. Kearney's top 10. And the most global centres are far from the most liveable.

Decision-makers and the wealthy presumably value lifestyle. And global communications have made it easier to do business remotely. The logical extension of that is that cities with a high quality of life should, over time, move up the rankings for global influence. Of course, some factors work the other way: the largest cities are generally better connected, and the very rich can overcome their cost disadvantages, which deter the merely affluent.

Austria's city of music isn't likely ever to eclipse the city that never sleeps for global clout. Still, it's just possible that Beijing and Shanghai, neither famous for lifestyle, may face unexpected competition from the likes of Auckland and Vancouver.

CONTEXT NEWS

- The biannual survey of global cities compiled by consultancy A.T. Kearney, unveiled on April 2, shows New York, London, Paris and Tokyo once again in the lead, but an analysis of key trends in emerging cities suggests Beijing and Shanghai may rival them for global influence within 10 to 20 years.

- The survey measures business activity, human capital, information exchange, cultural experience and political engagement.

- Mercer, meanwhile, published its latest quality of living survey in November. Vienna topped the list, followed by Zurich, Auckland and Munich, with Düsseldorf and Vancouver jointly in fifth place.

- A.T. Kearney 2012 Global Cities Index: link.reuters.com/pus47s

- Mercer Quality of Living survey: link.reuters.com/qus47s

(The author is a Reuters Breakingviews columnist. The opinions expressed are his own.)

(Editing by Richard Beales and Martin Langfield)

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