Case Study: The large British company WPP, advertising giant

The multinational combine WPP may not be a household name, but many of the companies it owns are extremely well known. They include the advertising agencies J Walter Thompson and Ogilvy & Mather and the public relations companies Burson-Marsteller and Hill & Knowlton.

All are among the leading players in the world in their fields.

WPP companies also deal in health care, consultancy, marketing, promotion, research and product branding. With a £4bn turnover, a staff of 65,000 and interests in more than 100 countries, WPP is the second-largest combine of its type in the world and is at the forefront of what might be termed the modern, service sector-based economy.

Doing a lot of business in mainland Europe, WPP has to deal in dollars, euros and, of course, sterling. And it is sterling that makes its commercial life much more complicated than it really has to be.

Sir Martin Sorrell, the group chief executive who founded the company in 1986 after leaving Saatchi & Saatchi, now believes that Britain should enter the eurozone as soon as possible.

He said: "Putting aside the political and emotional considerations, life for us would be simpler and easier on a day-to-day basis if we just had one currency to worry about. It simplified matters a great deal when we stopped having to worry about francs and pesetas and so on. Now it would make things even better if we did not have to deal in three different currencies. It's just less complicated. Of course, ideally, we'd like just one currency, but I don't think that is likely to happen.''

Sir Martin, who is a backer of Britain in Europe, was among many leading businessmen who signed an open letter to Tony Blair last month, saying that they believed the conditions were right for British entry to the euro. They also warned that the economy could be fundamentally damaged by a decision to stay out.

He said there were instances when WPP had suffered commercial disadvantage because Britain lay outside the eurozone. He believed that, ironically, the company might have lost the European Central Bank contract to advertise the campaign for the euro simply because it was based outside the eurozone. He said: "European community contracts tend to go to businesses that trade in euros in the eurozone.''

Sir Martin's views carry more weight than the average businessman: not only is he held in high regard in the City because of the way he has built up WPP from almost nothing, but the Government has also used his expertise on a number of advisory committees.