Martha Lane Fox is on the brink of becoming one of Britain's youngest multi-millionaires. But she admits she is paying a heavy price, writes David Duffy.

The former Oxford High School pupil and Oxford University graduate often leaves work at 2am and is back at her desk at 8am.

She is the driving force behind online holiday company lastminute.com, which is to seek a listing on the London Stock Exchange in a move set to turn its co-founders into multi-millionaires.

The website, launched two years ago by Ms Lane Fox and Brent Hoberman, will be capitalised at about £400m, according to City speculation. She says: "I don't want to be working these hours for ever. I hope that if I put in the hours now it will pay off in the future."

Ms Lane Fox - who celebrated her 27th birthday this week - and Mr Hoberman, 31, own 20.1 per cent between them - a combined stake worth £80m under the expected valuation.

The two Oxford graduates met in 1994 while working at a management consultancy. They set up the site with initial backing of £600,000.

"It was Brent's idea and I actually told him it was not a very good one when I heard it," Ms Lane Fox admits. She says her focus has not been on making money, but on building lastminute into a "fantastic company". The entrepreneurial pair had to borrow millions from investors and then beg, plead and cajole big names in the travel industry to take a chance and work on their Internet site.

The gamble paid off and now the website, which offers last-minute airline tickets, hotel rooms and package holidays, boasts more than 800,000 subscribers in Europe, and employs 80 staff.

Ms Lane Fox says she frequently worked until 2am while building the company.

"Setting up lastminute has been the most difficult and terrifying experience of my life," she says.

But her family - founders of the prestigious Oxfordshire estate agency Lane Fox - is making sure her new-found fame doesn't go to her head.

She adds: "My father is a don at New College, Oxford, and likes gardening. He hardly knows how to use a computer. So my parents are proud, but don't really understand, They keep my feet firmly on the ground." Her role at the company involves everything from securing new investment to recruiting senior staff at home and abroad. She also writes much of the Internet copy and the weekly e-mail, and still finds time to build supplier relationships.

The company, which has bases in the UK, France, Germany and Sweden, plans to expand further in the UK and internationally.

The group is seeking a listing both on the London Stock Exchange and the US technology-dominated Nasdaq with up to 25 per cent of the group's share capital expected to be offered to subscribers at flotation.

Amateur investors should beware of backing Internet stocks without taking expert advice, warns Sir John Harvey-Jones, former ICI boss and TV personality.

At an conference yesterday organised by investment fund house Framlington, he said: "You need to be with somebody who is watching the whole scene like a hawk. I expect that 90 per cent of Internet start-ups will fail.

"While there is huge investment potential, many people who leap into fashionable hot stocks will get burnt."

Story date: Friday 11 February

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