(FORTUNE Magazine) – ARE WOMEN OUTSIDE THE ENGLISH-speaking world finally getting to the top of the corporate heap? A glance at FORTUNE's fourth ranking of the most powerful women in business outside the U.S. certainly makes it seem so. Anne Lauvergeon, a Frenchwoman who runs Areva, France's state-owned nuclear power company, knocked off the perennial No. 1, American Marjorie Scardino, CEO of Britain's Pearson, who has been at the top of our list since we first published an international ranking. Scardino fell to third, behind Xie Qihua, the 61-year-old chairman and president of Shanghai Baosteel, China's largest steel company.

But read further down the list, and you'll find lots of Americans. Four of the top 15 on the list, to be precise. They include Scardino; Nancy McKinstry (No. 4), who runs Wolters Kluwer, the Dutch publisher; Linda Cook (No. 7), the head of Royal Dutch/Shell's gas and power division; and Rose Marie Bravo (No. 13), CEO of fashion firm Burberry. In Australia, American Dawn Robertson (No. 30), a former Macy's executive, has the top position at Myer, one of the country's biggest retailers. (By the way, FORTUNE decided that women on last year's list who live in the U.S. and work for American multinationals but oversee foreign operations are no longer eligible for the international list. That knocked off GM's Maureen Kempston Darkes, Coke's Mary Minnick, and McDonald's Claire Babrowski.)

Why have these Americans been able to break through the glass ceiling abroad? Are they smarter, better educated, more experienced, pushier? The answer varies from company to company, but there's one common factor: American women have had more time to climb the corporate ladder. Says Cook, the highest-ranking woman at Shell, who recently joined that company's powerful committee of managing directors: "They started earlier in terms of aspiring to have careers and studying technical disciplines."

In the U.S. women hold nearly 46% of managerial and administrative jobs, a higher percentage than nearly any other country, according to the International Labour Organization in Geneva. The difference is even more striking at the top executive level: Women in the U.S. have 13.6% of the board seats, compared with 8.2% in Australia, 8% in Germany, and less than 5% in France. "In the very top management, the U.S. has advanced more than any other country," says Linda Wirth, director of the ILO's bureau of gender equality. The same pattern holds true in business schools. Only 20% of the MBA candidates at Insead, the graduate business school outside Paris, are women. At Harvard Business School, by comparison, about a third of the class has been female since the mid-1990s. Many of those American women seek international jobs to broaden their experience.

With fewer non-Americans training for business careers, there are fewer available for promotions. "If you look at Continental Europe, there are not yet a lot of women at senior levels," says Nancy McKinstry, who became CEO of Wolters Kluwer in 2003. "So for a large multinational looking for a CEO, the pool of women is much smaller." Then there's the fact that in many Continental European countries, the big expenses of life--pensions, health care, and education--are still largely paid for by the government, so the need for women to work isn't as keen as it is for American women. "Do I see ambitious women in Europe? Of course," says McKinstry. "But in Europe, there is a much stronger emphasis on the balance between work and personal life." Many women do work, but only part-time. "You can't become CEO by working three days a week," says McKinstry.

But as companies globalize and tap talent around the world, more women, regardless of their origin, are likely to move into higher levels in business. "We had a kick-start in the U.S.," says Shell's Cook. "It's just a matter of time."