This month - just over a year after the paper's ‘Berliner' relaunch - his Guardian remit has been extended to provide strategic comms and crisis management for the group. The company has also created a head of comms post (filled by Trinity Mirror Group corporate comms manager Chris Wade), showing the growing significance it places in corporate comms.
The London office of Williams, 44, is certainly a long way from where he began his media career at the Salisbury Journal, where his duties included being Stonehenge correspondent (‘not exactly a full-time job'). After winning a production traineeship, he then spent six years at the BBC, including stints on Newsnight, Crimewatch and Film 90/91 with Barry Norman. ‘Working with presenters is very good preparation for working with difficult people,' he says.
A six-year spell at production lobbying group PACT introduced Williams to the world of corporate affairs.
He then took the most senior comms post at Carlton after the incumbent - Cameron - left. Williams describes as ‘extraordinary' the number of calls he has received from people ‘digging for dirt - not that there is any' on the Tory leader. He jokes: ‘For some reason, Cameron believed that his career in politics might be more productive than his career in PR.'
Williams joined Carlton at a tumultuous time - the run-up to the Granada merger, when ITV's advertising ‘fell off a cliff' and ITV Digital collapsed. Chairman Michael Green was notoriously difficult to work with, although Williams relished the challenge: ‘He could have a rage and then it would be forgotten, but he was often right.'
Green describes Williams as ‘very hard working, very popular and a great loss... Shaun and David were two of Carlton's finest'.
Williams's current role must seem comparatively stress-free. The Kent University French graduate is certainly relaxed during PRWeek's visit: ‘I don't worry at all. What's worrying me at the moment is that I'm having my bathroom fitted, and getting married in four weeks.'
That's not to say all is smooth. ‘Doing a PR job in the media is different to other PR jobs. The media self-obsession is utterly extraordinary,' he asserts. ‘The ability of newspapers to bite chunks out of each other - whether it's snide little diary stories or little pops on the business pages - must leave readers utterly baffled at times.'
He also argues that the climate can be even more treacherous for the ‘values-driven' Guardian than for more corporate rivals: ‘If The Guardian runs a leader about fat-cats in the City, someone's going to try and have a look at salaries here. They are looking for opportunities to have a go at us.'
There is also the ‘Guardian reader' stereotype. Williams admits: ‘There is a legacy that takes some time to undo. It is just as everyone thinks that Telegraph readers are crusty majors living in Kent. That's not true either.'
And there are the more serious issues, notably correspondent Rory Carroll's kidnapping in Iraq last year (which ended with his release unharmed): ‘It was literally a matter of life and death. We had to make sure the media knew that he was Irish, and that the Guardian's coverage of Iraq had been very against the invasion. It was awful, and we were very lucky.'
The Guardian is widely seen as a leader in the new-media sphere but the challenges posed by social media, Williams says, affirm his belief that organisations - and their PROs - must be as transparent as possible: ‘The days of organisations being able to hide things are gone.
‘Those who believe you can live by the spin are the ones whose reputations are going to suffer most.'
‘Frankly,' insists Williams, with characteristic unwavering confidence in the Guardian brand: ‘If there is something you can't explain adequately, you have to go and address why that is internally.'
CV - Shaun Williams
Director of corporate affairs, Guardian Newspapers Limited
Director of corporate affairs, Carlton Communications
Deputy chief executive, rising to chief executive, PACT
Senior producer, The Sunday Programme
Graduate production trainee, rising to film/studio director, BBC
Senior reporter, The Salisbury Journal and Times series