It is a moot point which mythical beast is the most difficult to construct - Harry Potter's hippogriff or a convincing argument that this Government is keen to lighten the regulatory burden on business.

William Sargent, 51, has done both. His Framestore CFC has provided digital effects to Hollywood blockbusters, winning an Oscar for the panzerbjorn, or armoured polar bear, in The Golden Compass, just out on DVD.

Since 2005 he has also been chairman of the Better Regulation Executive, set up that year with the aim of simplifying regulation in both the public and the private sector.

Born in Dublin, he is part of the Irish diaspora that arrived in the UK in the 1980s, despairing of their prospects in their native land. He started his first business of necessity while still a student at Trinity College, hiring out sound equipment to, among others, bands such as Thin Lizzy.

“The thing about Ireland is that we didn't have the generous university subsidies that there were in the rest of the British Isles,” he explains. “I did business and law - my last lecture on Friday, mercantile law, finished at 10am. By 11.30 I was delivering equipment, going from pub to pub, club to club, finishing at six in the morning.” Ireland, in the days before the Celtic tiger, was a Third World economy, he says - of his class at Trinity, only one remained in Dublin.

His first job in Britain was with the Cambridge firm that had supplied the sound equipment he had been hiring out as a student. He set up Framestore with his partner Sharon Reed in 1986 - they married in 1991 and have two teenage children - using digital techniques to manipulate video.

In those days computer-generated imaging, or CGI as it would become known, was in its infancy. It could be used only on video, because the processing power then available was inadequate for film. He risked £750,000 of capital to buy equipment from Quantel that was not even designed for the purpose he intended and sold time on it to creative businesses in Soho, London's media hub.

“When we started in 1986, we knew we would work on film eventually. We just had to wait for Moore's Law to run its cycle.” Moore's Law, named after an American cybernetics pioneer, states that computer processing capacity doubles approximately every 18 months. Manipulating film takes about 16 times' more capacity than video. Moore's Law did its stuff; Framestore now works for the big Hollywood studios, as well as the BBC, ITV and other broadcasters and advertising groups such as Martin Sorrell's WPP.

The firm created the god-lion Aslan in Prince Caspian, which opens this summer. That Oscar-winning digitised bear in The Golden Compass has as many hairs as a real one. Framestore was responsible for the startling opening scene in the epic Troy, of the huge Mycenean fleet sailing to attack the City. The inner geek in me kicks in; the fleet was far bigger than any such Bronze Age civilisation could have mustered, surely? He laughs. “You have got to remember this is Hollywood. They didn't have Brad Pitt, either.”

The company now employs 800 people and is one of the four leading special effects studios today, rivalling George Lucas's Industrial Light and Magic, which made the Star Wars cycle, and Peter Jackson's New Zealand-based Weta Digital, the creative force behind the staggering special effects in the Lord of the Rings trilogy.

Framestore made Walking With Dinosaurs for the BBC; Mr Sargent once joked that “every year the BBC wants more dinosaurs for less money. It's not a bad discipline.”

How does it work? “The director says: ‘I want XYZ to happen.' Creating a talking lion becomes totally normal. If you look at it and you think it's artificial, we've blown it.”

London is particularly well placed to gain such business, Mr Sargent insists, because Britain excels at mixing creativity with business. “This is one of the strengths of the British character. Hollywood directors love working in England.” We just get on with the job in hand, he says, rather than constantly aspiring to be something else. “In Hollywood, everyone says, I've got this script ...”

About 15 years ago he was asked by the European Commission to join a working party that was looking at High Definition TV, a concept that took the intervening years to arrive. “The DTI, as it was [the Department of Trade and Industry, now the Department of Business, Enterprise and Regulatory Reform], discovered I existed. I got a call saying: ‘Who are you, because you aren't on our radar?' I operated in a world oblivious of the government.”

He was asked to chair the Small Business Council, which advised Whitehall of the impact of government initiatives on business. From that came the Better Regulation Executive, part of the DBERR, where his job makes him the equivalent of a Permanent Secretary in the Civil Service. He is also a non-executive director on the board of the Treasury.

The BRE's job is to deliver regulatory reform by lessening administrative burdens on business and on the public sector. He is, he insists, on track for the stated aim of taking £3.5billion of costs out of the economy by May 2010.

“I live in a regulated world. I want to live in a regulated world. I don't want to live in an unregulated world.” So after his work on the Small Business Council, he decided that the job of improving the regulations that exist was “unfinished business. The place to do this was within the system, not outside the system.”

He rattles off a range of practical measures already taken. More than half a million small companies need not hold an annual meeting. The number of health and safety forms that must be completed by employers has halved. An accident at work can now be reported to a phoneline, rather than be wearyingly documented in a long written form. Car tax can be paid, or planning applications submitted, online. School visits by Ofsted now take two days rather than five.

It is not the general perception, I suggest tactfully, that the regulatory burden has lessened since 2005.“Perception always lags reality,” he insists.

But why does a successful businessman, the founder of a creative enterprise that is one of the leaders in its field, want to get involved with Whitehall and all that bureaucracy in the first place?

Mr Sargent says that he would be “horrified” to be offered a knighthood, seen as the inevitable reward at the end of such public service.

He does it for “personal development - my brain is exercised in a way it wouldn't be when running a business.” The scale of the task is staggering. “The Treasury rounds everything up to the nearest billion. In my business, we round up to the nearest pound.”

There is an altruistic motive, too. “I don't think you can just sit on the sidelines and not take responsibility for the world you are in but just moan about it.”

William Sargent

Born Dublin 1956

Education Primary school and childhood in Rio de Janeiro, Brazil. Secondary school: Jesuits at Clongowes Wood College, Co Kildare, Ireland. Trinity College, Dublin.

Career First business experiences - Band Centre in Dublin and HH Electronics in Cambridge

1986 Founded Framestore, now Framestore CFC

2000-04 Chairman, Small Business Council

2005 Chairman, Better Regulation Executive

2005 Non-executive director, HM Treasury (2005 to date)

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