By Ian Youngs BBC News entertainment reporter

A transformation is happening to British television, with behind-the-scenes changes to who makes programmes and how much power they wield.

Big Brother is among the hit shows made by the independent sector

BBC director of sport Peter Salmon's move to an independent programme-making company is the latest sign of a shift in the relationship between big old broadcasters to buoyant young firms.

Independent production companies make many of the UK's favourite programmes for all channels - from My Family on BBC One to Footballers' Wives on ITV and Big Brother on Channel 4.

And thanks to current changes to broadcasting rules, they are making more shows - and more money - than ever.

That makes them attractive destinations for executives like Mr Salmon and former BBC One controller Lorraine Heggessey.

The biggest boost to the indie sector came last year, when independent companies were given ownership of the rights to the programmes they made.

Before, broadcasters kept ownership of programmes they showed - and could reap the rewards of DVD sales and deals with foreign broadcasters.

Footballers' Wives is made by independent producer Shed

Now, the rights go back to the production company.

"Independents are now able to run really profitable enterprises," according to Elaine Bedell, the BBC's independent executive - the corporation's ambassador to the indie sector.

"As a result of that kind of business growth, they're able to attract very, very senior people out of broadcasters."

Ed Waller, editor of specialist publishers C21 Media, says there has always been "an exodus of executives" from the BBC to the indie sector.

"That's a traditional move - but it seems to have been more pronounced of late," he says.

Another big change on the horizon is the chance to make more programmes for the BBC.

The BBC is there to provide the best programmes for the licence fee payer regardless of who makes them John McVay Pact

The corporation must currently get 25% of programmes from independent producers.

But the government has said the BBC should do more to make sure it puts "the best ideas on screen".

So the BBC is to throw another 25% open to tender to both indies and BBC producers in a scheme known as the "window of creative competition".

Indies will pitch ideas against staff programme-makers for that slice of the budget. "The principle is the best idea will win," Ms Bedell says.

"We want the very, very best of in-house ideas and the very, very best of indie ideas to be coming to the BBC so that benefits the audience."

They're much more of a promising proposition to the City Ed Waller C21 Media

But Pact, the trade body of independent producers, says an extra 25% is not enough.

"The BBC is there to provide the best programmes for the licence fee payer regardless of who makes them - that's all the licence fee payer cares about," chief executive John McVay says.

"But you've got to have a system in the BBC which will commission the best idea, regardless of who makes it."

The combination of more shows, with more opportunities to make money, has made indies hot properties.

"They're much more of a promising proposition to the City," Mr Waller says.

There has been a fundamental transfer of rights value from broadcasters to producers David Frank RDF chief executive

"Previously, they were just workers for hire, they didn't retain any rights, they went feast-famine.

"They didn't actually own anything long-term, they didn't present any sort of investment vehicle for City people.

"But now they have a treasure chest of rights that can tide them over through lean years, they can present themselves as an investment vehicle."

Shares in Shed, which makes Footballers' Wives and Bad Girls, shot up 30% on the day it floated on the stock market last month.

And RDF Media, the company behind Wife Swap and Faking It, is set to join it on the stock market.

"There has been a fundamental transfer of rights value from broadcasters to producers," RDF chief executive David Frank said recently.

US expansion

Such companies are now also looking across the Atlantic - where the rewards can be even greater.

"Even if you make a pilot for a broadcast network over there and it fails, you'll get more money than you would if you made a series for the BBC," according to Mr Waller.

But Pact says while the industry is getting stronger, talk of a shift in the balance of power is premature.