DRAINEAUX:

While the precise number of French nationals in the U.K. is impossible to pin down since registration is not required, one French official offered an estimate of between 200,000 and 250,000, including 20,000 French university students. Add to that the sizable French populations in Belgium and Switzerland and you have a brain drain that France will want to reverse if it can.

London's two biggest attractions for French expatriates -- jobs and schools -- mirror the two major reform challenges for the French government. French schools abroad like the Winston Churchill lycée are popular with well-heeled French here, but they are far removed from the troubles besetting France's highly centralized education system generally, including declining student test scores, a negative classroom environment and a harsh grading system where failure is common. One in four students fails to complete secondary school in France and more than a quarter have to repeat at least one grade.

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