FIRST things first. What is a Miami-born former gym boss doing running London’s most sought-after investment club? “I’m an entrepreneur,” says David Giampaolo, chief executive of Pi Capital, grinning like a puppy. “I’ve always been fortunate enough to have people invest in me . . .”

So he thought it was about time he started investing in others. Hence three years ago Giampaolo stopped building gym businesses and took over Pi Capital, a respectable but low-key investment fund set up in 1998. Then he put his club-building nous to work.

Giampaolo had something rather different in mind for Pi from the usual, run-of-the-mill fund. He wanted to build a 250-strong club of senior executives, entrepreneurs and financiers, drawn from the business elite of Britain, who would pool money and know-how to back fledgling firms for possible bumper returns.

Bonkers? I think not — certainly not when Giampaolo, sitting in his Mayfair office, pushes across the table his club’s list of members.

Crikey! Most don’t want their names revealed, but among those who have already acknowledged their involvement are former Dixons chairman Sir Stanley Kalms, Alchemy boss Jon Moulton, Lastminute founder Brent Hoberman, Irish tycoon Dermot Smurfit, headhunter Ffion Hague and property scion Jamie Ritblat. Then there are the FTSE bosses, merchant bankers, serial entrepreneurs, even a famous scientist or two.

Giampaolo, 46, an increasingly visible presence on Britain’s business scene — “the most networked man in London”, according to one acquaintance — seems to have got his timing just right. “A decade ago Pi wouldn’t have worked. Now there is a lot more wealth around, and in the UK the tolerance to risk has increased.”

But investment funds and wealth advisers are ten a penny. Where Giampaolo has been smart is in creating something different with Pi, a mixture of casino ride and coffee club for top people, which seems to have caught the spirit of the age.

Hence Pi is not just about investment but involvement, too. You pay a £1,000 joining fee and £4,000 every year to stay in. For that, you get to see a raft of investment opportunities in early-stage companies that Giampaolo’s small team has filtered through; you don’t have to commit to anything you don’t like; and you can also offer deals to other members and provide advice on the opportunities Pi picks.

Then there are the club social events, lectures and lunches, all with the whiff of business celebrity attached.

Are these leaders lonely? Giampaolo’s thin face cracks into a laugh. No, he says, but sometimes it’s hard for business chiefs to get out and meet people at the same level. “You’d be surprised how many introductions I’m asked to make.”

Others have been quick to recognise the clout of Pi’s list. Michael Howard has already addressed its members. So has BA’s Rod Eddington. WPP’s Sir Martin Sorrell is pencilled in for June.

Hmm. Isn’t there something a bit iffy about elite clubs and secretive societies?

Come on, says Giampaolo, there is nothing secretive about Pi. Its members are simply pushing their wealth back into good ideas and giving other people a chance, while at the same time getting a sense of what might be stirring out there in the entrepreneurial jungle.

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