More than 10% of the best UK high-flyers were educated at a handful of prestigious private schools, new research suggests.
It also reveals that a degree from Oxford or Cambridge is vital for some professions, with more than half of the leading lights in the diplomatic service, the law and the civil service graduating from one of the two institutions.
The study, conducted by the Sutton Trust, looked at the educational backgrounds of nearly 8,000 people who featured in the birthday lists of national and Sunday papers last year by examining official website profiles, Who's Who and by direct contact.
It found that 10 elite fee-paying schools produced 12% of the leading high-flyers examined for the study.
Eton College - the former school of David Cameron, Boris Johnson, the Duke of Cambridge and Prince Harry - educated 330 high-flyers, a total of 4% of the UK's elite, the study says.
Among other former Eton pupils are Olympic gold medallist Sir Matthew Pinsent and actors Hugh Laurie and Dominic West.
Alongside Eton, the other nine top private schools, collectively teaching 12% of those whose education backgrounds were examined, are Winchester College, Charterhouse School, Rugby School, Deputy Prime Minister Nick Clegg's old school Westminster, Marlborough College, Dulwich College, Harrow School, St Paul's Boys' School, where Chancellor George Osborne was educated, and Wellington College.
Overall, almost half (44%) of the people studied went to private school, 27% attended a grammar school, 21% were educated at comprehensives or other state schools and 8% went to a former direct grant school.
The study found that the comprehensives producing the most high-flyers - with six people each - are Haverstock School, attended by Labour leader Ed Miliband and his brother, former foreign secretary David Miliband, and Holland Park School, which was attended by former environment minister Hilary Benn. Both are in London.
The research, due to be published later today at an event to mark the Sutton Trust's 15th anniversary, also looked at university education.
It found that overall, almost a third (31%) of high-flyers went to Oxbridge, and another fifth attended another leading university.
Some 62% of high-flyers in the diplomatic service are Oxbridge graduates, along with 58% of those in the law, and 55% of those at the top of the civil service.
But just 1% of top pop stars attended one of these two institutions, along with 8% of leading sportsmen and 8% of actors and actresses.
Sutton Trust chairman Sir Peter Lampl said: "This analysis shows how dominant leading universities and schools remain across the professions in Britain. That's why it is so important that access to our leading schools and universities is on the basis of ability alone."
In the last 15 years, the Sutton Trust has helped to improve access to top universities and shown ways in which leading private schools could be opened up on the basis of ability, he said.
He added: "But studies like this - and over 120 pieces of research commissioned by the trust since 1997 - show how far we still need to go to improve social mobility in this country and ensure that every young person can achieve his or her potential, regardless of their family background."
The study examined the educational background of leading individuals working in business, finance, the arts, education, public services, sport, law and journalism.
Education Secretary Michael Gove has in the past described the dominance of the public schoolboy prominent roles in British society is "morally indefensible".
In a speech to independent school headteachers in May, Mr Gove said the sheer scale of privately-educated men in positions of power in business, politics, media, comedy, sport and music was proof of a "deep problem in our country" which politicians have failed to tackle with "anything like the radicalism required".
Lord Moynihan, chairman of the British Olympic Association and himself public school-educated, raised the issue of public school dominance in British Olympic sport in the run up to the London 2012 Games, saying: "It's one of the worst statistics in British sport."
Last week research from the Sutton Trust revealed able students are put off applying to the most selective institutions by the cost of living, distance from home and future job prospects.