These boots are made for your CD player

There are two things that unite the nation across class, race, age and sex - tea and Dr Martens. They make up our common currency from the highest to the lowest. Dr Martens is as powerful a brand in the UK as global hypernames like Levi's and Coca Cola and when you're as loved as that, you can probably get away with anything. So, Dr Martens is seeing just how far it can go.

The shoemaker has launched a record label, called, unsurprisingly, Dr Martens. The label plans to break up-and-coming new talent, although the first release - an LP titled Generation To Generation - is a bit of a re-hash of Eighties mod tracks, featuring acts such as The Lambrettas and The Untouchables. On the new music tip, current indie-pop types like Box Office Poison throw down a cover version of "Louie Louie" and Lynus do a low-fi version of "My Generation". The CD is a giveaway in Dr Martens stores, for the time being so hurry, hurry, hurry.

Simon Mills, marketing strategist for Dr Martens, says this record is just the first step. "What we really want to do is push young British talent to an audience who wouldn't otherwise get to hear them," he says. "We'll be releasing the record in all our territories around the world, through all our retailers, then we will see what the reaction is before progressing." Although Mills says he isn't planning to compete directly with established labels, they have enlisted the services of the indie production God, RC Writer. Writer's only other work is for Future Legend Records and he has turned down offers from other labels.

So why is Dr Martens doing this? It has a heritage in music-industry sponsorship through concert and festival involvement. But a record label? Well, these days, it's all about brand stretching. That means launching a product in a new market with a name made famous in a completely different, old market. That's how Cadbury manages to produce a cream liqueur, Harley Davidson makes aftershave, and the man from Del Monte has rustled up some cook-in sauces. The key to this is your brands "personality". In the world of brand personalities, Cadbury's means small pleasures, so a cream liqueur is OK.

Peter York, style guru and management consultant, has looked into brands' personalities and produced a three-star Michelin style-guide to stretching. Barclays, he thinks, is a Seventies-style high-street bank. Can it stretch? Not really. Coca Cola stands for the best American tradition for everyone. Can it stretch? Well, possibly. Virgin stands for David vs Goliath. Can it stretch? But of course.

"On paper, brand stretching looks like a good idea, brands are expensive to develop and if you have a particular appeal to a market segment why not try and sell them something else?" says Chris Macleod, managing director of Benson and Hedges' ad agency CDP. "But I wonder how many brands are really that stretchy. Superficial relevance should not be confused with real, long-term consumer trust and credibility. If the new 'brand extension' fails to perform, what does this say about the parent brand?"

Mills is indignant. 'We have a genuine desire to support new British bands and that is why we're doing it. It's not just a marketing ploy. Our brand is big enough for us not to have to spend on conventional advertising, so we are able to support other avenues and not seek too much recognition from doing it."

Whatever the niceties of the argument, the Dr Martens brand stands for classic British workwear with a certain hard, urban authenticity. Now that everyone's obsessed with Keeping It Real, that brand image is about as cool as Britannia can be, so the only limit to the DM empire is our purchasing credulity. Dr Marten's clothes makes logical sense, and the record label connects to the shoe makers image but you're going to have to stretch a long, long way before you see Dr Marten follow Richard Branson into Bridal Wear. Although, you never know these days ...