For just the second time in six years, INSEAD jumped ahead of the London Business School to claim first place in the new Poets&Quant‘s ranking of the best MBA programs outside the U.S. INSEAD’s accelerated 10-month MBA, is the quintessential global experience, drawing students from more than 80 nationalities on three campuses in Fontainebleau, France, Singapore, and Abu Dhabi.

European business schools dominate the list, with all Top Ten MBA international programs in either the U.K., France, Spain, Italy, or Switzerland. Rounding out the top five programs are No. 2 London, No. 3 IESE Business School in Spain, No. 4 IE Business School in Spain, and No. 5 HEC Paris in France. HEC gained three places this year, from eighth last year.

Among the Top 25 schools, the biggest gainer was Canada’s Queen’s University, which jumped 30 places to rank 24th, up from 54th last year. Other major gainers on this year’s list include HEC Montreal, which rose 15 positions to finish 20th. The University of Hong Kong jumped 25 places to rank 27th, a big improvement from its 52nd place finish a year ago.

In a separate ranking of U.S. MBA programs, Harvard Business School edged out Stanford for top honors, followed by Chicago Booth, UPenn Wharton, and Northwestern University’s Kellogg School of Management (see the complete U.S. list here).

HOW THE POETS&QUANTS RANKING IS PUT TOGETHER

This new P&Q list is a composite of four major MBA rankings published by The Financial Times, The Economist, Bloomberg Businessweek and Forbes. The ranking takes into account a massive wealth of quantitative and qualitative data captured in these major lists, from surveys of corporate recruiters, MBA graduates, deans and faculty publication records to median GPA and GMAT scores of entering students as well as the latest salary and employment statistics of alumni.

By blending these rankings using a system that takes into account each of their strengths as well as their flaws, we’ve come up with what is arguably the most authoritative ranking of MBA programs ever published. The list tends to diminish anomalies and other statistical distortions that often occur in one ranking or another. Instead of simply merging together the four rankings, P&Q weighs them according to the soundness of their methodologies (The FT and Forbes are both weighted 30% each, while the BW and Economist rankings are each given a 20% weight.) A composite list lends greater stability to a ranking of schools that rarely change from year to year.

More so than rankings of the U.S. schools, individual rankings of international MBA programs can be widely erratic, in part because rankings can markedly differ on each of the four major lists. The Economist, for example, assigns numerical ranks to many non-U.S. MBA programs that don’t even make The Financial Times‘ ranking and the same is true of the FT. The Indian Institute of Management at Ahmedabad, widely counted among the very best business schools in the world, is not even ranked by The Economist. The school is ranked 12th among non-U.S. schools, however, by The Financial Times. Just as puzzling, HEC Montreal, ranked by Forbes, Businessweek and The Economist, fails to get a ranking from the FT.

RANKINGS FOR INTERNATIONAL SCHOOLS CAN VARY DRAMATICALLY

And even for any individual school, rankings can vary dramatically. Consider Western Ontario University’s Ivey School of Business. Businessweek recently crowned the school No. 1 in its latest ranking, but The Financial Times puts it at 48th among non-U.S. MBA programs and just 97th overall. The Economist ranks the school 27th best outside the U.S., but Ivey isn’t ranked at all by Forbes.

Schools that are recognized across all four rankings can be interpreted as more solid and credible than schools that may only receive a single ranking. That is why the P&Q list gives greater weight to MBA programs that are more widely ranked and less weight to those that are not.

The lesson here is simple: Take all these rankings with a very big grain of salt. The reason results that don’t seem to coalesce around a single number has to do with the different methodologies employed by each ranking organization. Those approaches are made up by journalists who often know very little about graduate management education. So peculiar, if not nonsensical, results in any one survey are not unusual.

THE SCHOOLS THAT DISAPPEARED AND THE SCHOOLS THAT MADE A DEBUT

INSEAD edged above London by the smallest of margins–an index score that was just .9 above LBS, a feat accomplished largely because of London’s relatively weak No. 9 finish in The Economist ranking among non-U.S. MBA programs.

Schools toward the end of the list are particularly vulnerable to falling off from year-to-year. That’s because they are typically ranked by only one of the four major global rankings, a precarious perch, for sure. This year five business schools disappeared from our international ranking, because they are no longer ranked on any of the four major lists: China’s Peking University, which had been ranked 46th, Coppead Graduate School of Business in Brazil (51), Aston Business School (61) in the United Kingdom, Audencia Nantes School of Management in France (62), and Yonsei University in South Korea (68).

The newcomers this year? The University of Alberta in Canada, which debuted in 56th place, ESIC Business & Marketing School in Spain (59), Copenhagen Business School in Denmark (60), Trinity College Dublin (67), Ryerson University’s Rogers School of Management in Canada (68), and the University of Liverpool (69). All of which should remind readers that MBA programs which rank on at least two of the four lists are sure bets on quality and reputation.

(See following pages for our tables ranking the top non-U.S. MBA programs)

DON’T MISS: OUR VIDEO INTERVIEW WITH INSEAD ADMISSIONS DIRECTOR PEJAY BELLARD