Andy Duncan: Channel 4's chief writing the script for what's next on TV

7am

As a state-owned but commercially funded broadcaster, Channel 4 has always been a unique kind of business. But, in a twist on the traditional Chinese curse, now is an even more interesting time to be in television. Audience fragmentation is playing havoc with advertising revenues. The global economy is of increasing concern. But most important of all is the looming digital switchover, with its potentially terminal implications for Channel 4's public service role, and associated subsidies.

Such questions are all in a day's work for the channel's chief executive. "We are a hybrid," says Andy Duncan. "In one sense we are non-profit, but in another we are aggressively commercial. My typical day straddles the divide."

After breakfast with the children at home in Chaldon in Surrey, Mr Duncan takes the train into central London, picking up a cappuccino in Victoria station on the way.

9am

Arriving at Channel 4's ultra-modern offices in Westminster, Mr Duncan has just enough time to check through the first wave of emails before plunging into the day's round of meetings.

First, he heads over to Parliament to address the media and communications groups on the subject of "convergence". As much as the internet spells doom for traditional media, it also has massive potential. "We used to be just the single Channel 4, but our future is all about multimedia," Mr Duncan says. "We are already doing a lot with digital channels – we have E4 and More4 and Film4 and so on – and we are now also increasingly looking at new platforms."

10am

Back to the office for the first internal meeting, with the programming and finance teams, to look at forecasts for the coming year. Viewers are being tempted away by multiple pay-TV channels, video-on-demand and the internet, and ad revenues are not what they used to be. In April, Channel 4 reported profits of £1.6m, compared with £21.3m in 2006, and £66.8m the year before. The £600m programming budget is under pressure, and tough decisions must be made. "There is not as much money as we would like, so part of the decision is about prioritisation and how to spread not quite enough money in the right way," Mr Duncan says. "The question is how much we can afford to spend next year, and how much should be spent on Channel 4 itself, how much on digital, and how much on the 4OD on-demand service."

Decisions must also be taken about the balance between comedy, drama and entertainment.

11am

With just enough time for a quick update on Big Brother, it is on to the most important session of the day: to put the finishing touches to Channel 4's submission to Ofcom's review of public service broadcasting (PSB). For Channel 4, there is no bigger issue. In March, it published the "Next on 4" strategy, a plea to the Government to shore up its falling income with a £150m-a-year subsidy. Today's meeting is to be sure the Ofcom submission does the argument justice.

The spur for the review is the 2012 digital switchover, when the analogue television signal will be turned off and the slide away from the traditional free-to-air broadcasters will become a flood. It is not just about money, it is about ensuring that the BBC is not the only option, Mr Duncan says. "The UK public wants high-quality programme investment, and they want plurality. Although others can make a limited contribution, it will fall to Channel 4 to provide that plurality."

In a darkening economic climate, there is no time to waste. "From our point of view there is a growing urgency – there is a downturn in the ad market, so it is key to get decisions, and solutions, quickly."

1.30pm

Lunch – most likely just a sandwich. "Sometimes I have a business engagement but most days I try to be at my desk and catch up on emails and papers."

Then it is straight downstairs to host an event the channel is running as part of the Government's creative industries apprenticeship strategy. Ed Balls, the cabinet minister for schools, is there to make a speech, as is Andy Burnham, the Culture Secretary. Mr Duncan finds time for a quick chat with Mr Balls about Channel 4's educational activities, and with Mr Burnham about the future of DAB digital radio.

4.30pm

The DAB update leads neatly into Mr Duncan's next meeting, with the New Business and New Media directors to discuss the future direction of 4OD and the channel's various websites, as well as the plans for 10 new digital radio stations following Channel 4's successful bid for a licence last year.

Then it is straight on to see the advertising sales teams for the regular review of the ad market and Channel 4's share. The picture is not rosy. "Our major revenue today is from ads, and there is downturn coming, so we are being quite careful," Mr Duncan says. "For the first half of the year, the market was down about 1 per cent, and we are now beginning to see the first worrying signs that it is getting worse."

From there, it is on to an update with the marketing team, to run through the advertising campaigns that are coming up. There are also the inevitable discussions about budgets and how to prioritise the marketing spend for the rest of the year.

6pm

With the day's meetings dealt with, it is back to the desk for a final scan through the inbox. There are also responsibilities to be discharged as chairman of the Media Trust, an industry charity, and head of the Royal Television Society's Futures initiative, which aims to get more young people into television.

If there is no evening function to attend, Mr Duncan expects to be home to the family by about 7pm, in time for his multiple sporting activities. Monday night is friendly five-a-side football night at the local club, but he also plays hockey for Oxted in Surrey and represents his tennis club in interclub tournaments. "I also play golf when I can," he says."I would love to play more corporate golf, but I just don't have the time."

The CV

Name: Andy Duncan. Age: 45.

Marital status: Married with two children, aged nine and 13.

Education: Whitgift School, Croydon; BSc in management sciences, University of Manchester Institute of Science and Technology.

Career: Joined Unilever in 1984 and spent 17 years working his way up the marketing ladder. In 1999 was named European category director for Unilever food and beverages. Moved to the BBC in 2001 as director of marketing, communications and audience. Oversaw launch of digital TV and radio and Freeview.

Appointed Channel 4 chief executive in 2004.