For super-wealthy Russians, education at one of Britain's top traditional boarding schools has become as desirable as a pad in Mayfair. Kitting out your little Boris or Svetlana in boaters and blazers has a particular cachet, and that is unlikely to change even if sanctions affect Russia's relationship with the West.
Education has become one of the U.K.'s most successful exports. In the 2012-13 school year, the fee income from international students was about £685 million ($1.1 billion) - and the number of pupils from Russia increased by 27.4 percent, to 2,150, the third-quickest rate among non-British students.
And since 2004, the number of Russian students at British "public" (ie private) schools has more than tripled, according to the Independent Schools Council.
"There is nowhere else that really does education like this system. These schools look more like Harvard or Yale," William Petty, co-director at Bonas Macfarlane, the high-end tutoring firm which gets around 60-70 percent of its consultancy business from Russians, told CNBC.
One of the early examples of the modern breed of U.K. educated Russian elite is Kirill Makharinsky, son of oil and gas investor Leonid, who went to Eton, got a first at Oxford, and is now an internet entrepreneur who founded Russian travel site ostrovok.ru.
For rich Russians, part of the attraction of these schools is their difference from their own country, with separation of the sexes and full time boarding.
The English countryside, where most of the more prestigious boarding schools are located, is seen as a safe place for those who might be vulnerable to kidnapping. The education itself is viewed as the best in the world – and the network built by being at school with future Prime Ministers and captains of industry can be second to none.
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Fictional representations from Hogwarts to Malory Towers have helped fix the British boarding school as a symbol of aspiration. The U.K. has a lucrative line in education exports, which have grown from £14.1 billion in 2008/09 to £17.5 billion in 2011 according to UK Trade & Investment.
And the contributions to the U.K.'s economy don't stop with fees of up to £40,000 each year.
"The children will buy uniforms, and burgers when they go into town, and the parents will come and stay in a good hotel and spend money on flights," Hilary Moriarty, director of the Boarding Schools Association, told CNBC.
Headmasters around the U.K. are keeping a close eye on enrolment figures for this year, in case the sanctions imposed on Russia over the annexation of Crimea have any effect. The main side-effect so far has been an uptick in wealthy Ukrainians trying to get their children into British schools, according to Petty.
Marlborough, where the Duchess of Cambridge and Samantha Cameron, wife of the British Prime Minister, studied, Wellington and Arundel have become increasingly popular.
The increasingly international nature of the U.K.'s independent schools is down in part to a domestic decline. During the latter part of the twentieth century, some of the country's top private schools hit financial difficulties as parental attitudes towards boarding changed. The credit crisis proved the final nail in the coffin for some schools – and sent a warning to others that they had to cast their enrollment further afield to survive.
More than half the girls at Roedean, the leading independent girls' school, are now from non-British backgrounds, after a concerted effort to address falling numbers.
Helping the children of wealthy Russians get in to establishments like Eton or Harrow has become a lucrative industry.
There has been a notable shift in recent years since the introduction of psychometric testing, which means that the "down at birth" system, where parents put their children's names down for the most prestigious schools as soon as they were born, has faltered.
The most important point is preparation for the entrance examinations and interviews for public schools. Companies like Bonas Macfarlane, which charge around £10,000 to place a child in a British public school, will work out where your child has a chance of getting in, and prepare them for the psychometric tests which many top British schools use.
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The U.K.'s top schools are also now seeing a growing number of inquiries from wealthy Russians further down the pay spectrum from oligarchs and financiers, according to Petty. And the range of schools they want to get into has broadened.
"The days of someone coming off a plane and demanding you get their daughter into Eton (an all-boys school) are over," he said.
There have been grumblings from some old boys that their children are missing out – and that fees are being pushed up by the influx of foreign students, with an above-inflation average increase of almost five percent (4.97) between September 2011 and 2012. This may be the upper middle class equivalent of working class Brits complaining about competition from Polish builders.
"If their children aren't intellectually able enough to get into schools, it's not the fault of other pupils," Petty, an old Harrovian, said.