Jackson makes the grade at Channel 4

Channel 4 has appointed Michael Jackson, controller of BBC1 and director of television at the BBC, as its chief executive to replace Michael Grade.

Mr Jackson will leave his post almost immediately and is due to start at Channel 4 on 1 June, where he is expected to make big changes to the channel's output.

In the past he has been critical of its programmes, describing it as a "lager channel" chasing young, upwardly mobile men. Industry insiders believe that he will move the channel away from controversial youth programmes like The Girlie Show or Eurotrash. He is also known to believe that the award-winning Channel 4 News might need modernising - he was prevented from modernising the news while at the BBC. The Big Breakfast, which has just had its contract renewed, will be "looked at hard"according to sources close to Mr Jackson.

He is known to believe that many Channel 4 programmes, such as the pursuit game show Wanted, are good ideas badly executed. Quality control will be expected to improve and he plans an overhaul of the channel's loose commissioning structure. "There is a feeling that Channel 4 has got lazy," says the source.

There will be more of the "leisure interest programmes" that cover gardening, motoring or cookery and these may replace some of the channel's more obscure documentary strands.

Mr Jackson was responsible for BBC 2's late-night arts show The Late Show when he first joined in 1987 from a career as an independent producer for Channel 4. Latterly he has been credited with kicking off the costume drama boom by commissioning the BBC's adaptation of Middlemarch which was both a critical and ratings success.

However, not all of Mr Jackson's output has been highbrow. At BBC2, he was responsible for Fantasy Football - in which lager is actually drunk - The X-Files and Mrs Merton. "He is fantastically catholic in a way that no one else ever is," said Jane Root, head of the BBC's independent commissioning group and a friend of Mr Jackson's for 15 years. Currently his favourite BBC1 programme is the consumer affairs show Watchdog.

Mr Jackson was offered the job on 22 April, but has been negotiating to bring some of his own people with him. He has also been asking the channel's board to clarify the remit of the job and long-term strategy. The channel is planning an arts movie channel that will broadcast on digital television and is also interested in some form of overseas expansion.

Channel 4 insiders were depressed at the appointment. Mr Jackson defeated their popular director of programmes, John Willis, who is on leave; sources in the channel believe he will be the first of many departures.

Mark Thompson, the controller of BBC2, will temporarily take over Mr Jackson's roles at the BBC, and a permanent replacement is expected to be in place within the month.