Lygo's appointment will come as no surprise to the industry, as he had been hotly tipped to succeed Gardam. The appointment is viewed as a natural move for him and sees him return to the channel that he left two years ago when he joined Five.
He will take on a programming budget of £439m in his new post, almost three times the value of Five's £157m spend.
At Five, Lygo has been responsible for helping to change Five's image, partly through importing high quality shows from the US including 'CSI: Crime Scene Investigation', 'The Shield' and most recently 'Buffy the Vampire Slayer' spin-off 'Angel'.
Mark Thompson, Channel 4 chief executive, said Lygo was the obvious choice to replace Gardam.
"I had only one person in mind when it came to replacing Tim and so I'm delighted that Kevin has agreed to rejoin Channel 4. He has a great track record of attracting the best creative talent and of commissioning the type of original and provocative programming that is Channel 4's hallmark. I'm looking forward to working with him on the continuing reinvention of the Channel 4 schedule that has been proceeding so successfully under Tim's direction."
Lygo said that while he enjoyed his time at Five, he "couldn't pass up the chance to return to Channel 4".
"The combination of a bigger programme budget and the channel's remit to cause trouble and to innovate represents a unique opportunity for a channel controller and a challenge that I'm genuinely excited by," he said.
The move is the latest in a string of changes at Five, following the departure of Dawn Airey, who moved to BSkyB as managing director of Sky Networks, and the appointment of her replacement Jane Lighting, former chief executive of Flextech, in February.
Lighting, whose background is strong in programming and who has so far kept a fairly low profile since taking up her post at Five, has told staff she will take over programming following Lygo's departure until a replacement is found.
Although both broadcasters confirmed the appointment, there were few details available at the time of writing. Speculation indicates Lygo could join Channel 4 in the autumn, and he is expected to leave Five shortly.
In the last year, Five's audience share continued to grow to 6.3% in 2002, up from from 5.7% 2001, while Channel 4's share recently dipped to its lowest level in more than 10 years to 9.5%, down from 10% last year, according to recent figures from Barb. The broadcaster has come under fire for programming such as 'Boys & Girls', now cancelled, and its breakfast show 'RI:SE'.
Lygo first joined Channel 4 as head of entertainment and music in August 1997. During the next four years, he was responsible for an expansion of the channel's programming. He commissioned long-running hit shows such as 'So Graham Norton', 'Trigger Happy TV', 'Smack the Pony', 'Spaced', 'Black Books', 'Da Ali G Show', and 'The 11 O'Clock Show', as well as the notorious 'Brass Eye' special on paedophilia. Lygo also acted as controller for the successful launch of Channel 4's digital entertainment channel, E4.
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