The undercover story of a success

Marks & Spencer estimates that almost everybody will have worn a pair of its knickers at some point in their lives.

Thirty five per cent of the knicker-buying public buy their scants at M&S, and tourists and foreign visitors make the underwear department part of their itinerary.

It is little wonder. No one else in the world offers the sheer choice - from the sports bra to the honeymoon negligee - or the quality and value for money that M&S guarantees. And that is what singles out St Michael clothing. Customers know they can rely on the brand name to provide honest clothing that will never make them look ridiculous.

Behind the scenes at Baker Street, the cogs that keep the endless supply of pounds 12 cotton polo shirts in 16 assorted colours on the shop floors up and down the country are well oiled. Supply is in direct response to what the consumer wants; as people's lives become more leisure-oriented, Marks & Spencer expands into ranges for golfing, aerobics, and tennis.

The customer relations department at Michael House receives over 2,000 letters a week. People write in to thank the company, to tell them the history of a particular item of clothing they might have bought twenty years ago, and, sometimes, to complain. And complaints are taken seriously, often handed on to the on-site clothing technologists who will test, test and test again, examining fabric structures and seam strength. Every item of clothing is expected to perform to the best of its ability and that means it has to get past the wearer-trial panelists who will wear and wash their given item and fill in a detailed questionnaire.

Then there are teams of buyers who work with suppliers and specialist fashion consultants who have included Paul Smith for menswear, Betty Jackson, who is the main consultant on womenswear, as well as designers like Ghost's Tanya Sarne, who consults for Coats Viyella, who in turn, supplies M&S. Each buying department consists of a selection team with a senior selector and range selectors. Within the knitwear department, there will be a range selector whose sole purpose in life is to choose cardigans.

There have also been accusations from designers that the company has stolen ideas and fabrics (Antoni & Alison and Liza Bruce have both attempted to take legal action against M&S) but such is the power and influence of the company that there is little to be gained by such action.

Although the company relies on classics to appeal to a broad range of people, it is also canny in acknowledging the more fashion-conscious consumer too. So there are hipsters in store this summer, alongside the straight- legged slacks, and a range of polyester shantung shirts that have been featured in fashion magazines, including Vogue, as best buys. Such new ideas, that are usually more competitively priced than similar items available on the high street, help prevent the clothing lines at M&S from becoming too bland. They are never too extreme, however, for fear of frightening anyone off.

Before a new garment hits the shop floors, it will first have been tried on the St Michael house models - a team of perfect sizes 8 to 20, both men and women. If you want to have universal appeal, you must of course ensure that the stock fits across the spectrum.

The secret of Marks' success is in its packaging of new styles and fabric innovations into clothing ranges that the man, woman and child on the street has no difficulty understanding or wearing. When Lycra was introduced to M&S in the Eighties, it was tested on women's underwear, which it transformed in fit and comfort. It was then applied to men's underwear, which women, now educated in its wonders, bought for their partners.