Some of Lord Birt's methods have been scrapped

Hundreds of middle managers stand to lose their jobs - although exactly who and how many will not be clear, according to Dyke, until the new structure is in place.

The aim is to save money to invest in programmes, to speed up decision making and to create a new culture which Dyke calls "dynamic, creative and collaborative".

In practice much of the legacy of Lord Birt, who left in January, has been ditched by his successor.

In particular the split between BBC Broadcast and BBC Production, legacy of the last great Birtist upheaval, has been abandoned.

Broadcast ran the TV and radio networks and commissioned programmes from producers inside and outside the BBC. It had the money.

Production brought together virtually all the BBC's in-house programme-makers in a vast empire, entirely dependent for survival on how many programmes they could sell to Broadcast.

Red tape

Like much of the internal market, the split proved bureaucratic to operate. To improve that, Dyke is cutting the number of internal "business units" from 190 to around 50.

It also led to a haemorrhage of talented producers, to whom the BBC could no longer offer job security.

Dyke's solution is to end the Broadcast-Production split.

In future a director of television and a director of radio will run the channels, plus (in the case of radio) the BBC's music departments.

Programme-makers will be organised in four big groups. One will be responsible for news, one for sport, one for factual and educational programmes, and one for drama, entertainment and children's programmes.

New bosses

The reforms affect many of the BBC's most senior managers. Mark Thompson, currently running the BBC's national and regional operations, takes the powerful post of director of television.

Alan Yentob, former director of television, has been put in charge of drama, entertainment and children, with a brief also to nurture on-air talent and develop BBC-backed feature films.

Matthew Bannister, who had been boss of the huge production department, gets a new job in charge of just marketing and communications.

A new theory of how to manage public sector organisations now holds sway at the BBC. Out has gone Lord Birt's approach - to mimic the market-driven commercial world.

The new philosophy values leadership skills and aims at a "flatter" management structure in which decisions are taken swiftly by fewer people. The director-general is also much closer to programme-makers and broadcasters. But above all the aim is to save money.

Extra spending

This year Greg Dyke says the BBC has an extra �100m to spend on programmes, thanks to previous savings (much of the money will go to pay for the Olympics).

Next year he hopes his own savings will produce a further �200m. Some will almost certainly go to local radio, some will be spent on sport, where the soaring cost of broadcast rights, already astronomical and still rising, has hit the BBC hard.

Some will go on the new digital services, like a new children's channel, more educational programmes and more interactive services, for which the BBC has just received a rise in the licence fee of 1.5% above inflation.

And much will go on programmes - especially drama - for the BBC's flagship channel, BBC One.

As Greg Dyke knows well, he can rearrange the chairs at the top table as often as he likes, but if the BBC's popular audience deserts it, the game is well and truly up.