There was young Martina Doyle (now King), drifting along aimlessly but contentedly as a personnel clerk in Ken Livingstone's Greater London Council. Her mother, from Abbeyleix, Co Laois wasn't a bit happy. Martina was leaving the house one morning when she came across a subtle hint; cut out and glued to the inside of the front door was a job advert from the Observer.

She took the hint, got the job in tele-sales at the newspaper itself, and began a steep rise through the British advertising business. Within a decade she was sales director of Capital radio, becoming its managing director before moving to TSMS, which sells advertisements for around one third of ITV television stations, including UTV.

In October, she moved from a well-established medium to an unproven one, becoming managing director of Yahoo for Britain and Ireland. The move did represent a risk, but a calculated one. True, the revenue stream is at times hard to spot on the Internet, but few would argue that Yahoo is the Coca-Cola of Internet branding.

"As soon as I got there, it hit me like a train - Yahoo is a media company and like all Internet companies it needs to move from being in the technical department, with a few people who understand it into mainstream media. That is where it is almost beginning in the UK, and is heading in that direction in Ireland," she says.

The company asked her to be managing director, she added, because it wanted someone who knew the world of advertising, who could bridge the gap between the "early adopter" stage of any product and its mainstream adoption.

"Our revenue base is advertising, and I know the advertising community in Britain," she says.

She will not say how much advertising revenue Yahoo is bringing in from Britain and Ireland now, but insists it is already millions rather than thousands of pounds.

"What I can tell you is that the UK market in the year 2000 will probably be worth somewhere in the region of 2 per cent of the display market, and the UK display market next year is set to take in just under £9 billion sterling [€14 billion]," she says. "We think that by 2003, conservatively, the Internet industry should be able to take 7 per cent of the UK display market. Classified goes on top of that, then e-commerce goes on top of that again."

Yahoo is extremely well positioned worldwide, with 385 million Internet page views a day. The best-known Internet search engine, the company is also doing well in Britain and Ireland. According to the latest British statistics, 55 per cent of Internet users have visited the yahoo.co.uk site in the past two weeks, making it the most popular page. The BBC comes second, with 40 per cent, and Freeserve is third, with 27 per cent.

In Ireland, Ms King says, Internet consultant Amarach reckons Yahoo is also the most popular site.

The thing that brings people to Yahoo is the search engine, but that could change in the future, she says. With cable, telephone and other utility providers now racing to bring broadband, rapid Internet access to their customers, the economics of the medium will change.

The advert that appears on Internet pages now will stay, but there will be new options. For example, clicking on a page might open a video clip, or an audio file.

Yahoo has bought Broadcast.com, a company that specialises in broadcasting sound and vision on the Internet. To gauge how much demand there is for events online, the company recently broadcast a fashion show by the lingerie retailer Victoria's Secret. So many people logged on it crashed the computers designed to serve them.

"For someone like me who has worked in the press, and in radio and in TV, the most beautiful thing about the Internet is that it can do all of those things at once. We have the publishing capacity, and through Broadcast.com we can play out radio and television commercials," she says.

Also, the advert could be sourced through Broadcast.com, so that someone logging onto, for example, the Ritchie's Mints website, would automatically send a signal to Yahoo, which would then send that person the latest advert for those delicious mints.

Adverts can also be better targeted, with the server recognising where the user's computer is based, and sending text or video tailored just for that market.

"After that, the next challenge is that Internet connectivity doesn't just come through the PC, it will come increasingly through the television, through the mobile phone - there is even a microwave that has been designed to hook up to the Internet."

To meet the challenge, Yahoo continues to expand. The company has 1,700 staff worldwide, with 70 at its European headquarters in London. Ms King points out that unlike most Internet firms, Yahoo is already making money.

Last week, it appointed the Dublin-based Internet advertising agency Ican as its Irish agent, and she says she is delighted to be doing business here.

As soon as her parents retired, they sold up in London and moved back to Co Kildare.

"I am Irish - I was brought up in London but I consider myself Irish," she says.

"We are going to really work hard to develop our Irish content, so that when people search in our directory we would have a much richer field of Irish products, and also when someone is looking for news they would be able to find good Irish product there."

Sean Mac Carthaigh can be contacted at smaccarthaigh@irish-times.ie