Forty years on, Adel Rootstein's mannequins remain head and shoulders above the rest, says Hester Lacey
There's a small heap of severed hands and a few scalps lying on the desk in Michael Southgate's airy glass-walled office in West Kensington. Downstairs in reception, limbs and torsos are piled high. Southgate is creative director of Adel Rootstein, the world's premier manufacturer of display dummies, although dummy is certainly not a term used here. These are the Rolls-Royces of the shop window and are referred to, reverentially, as mannequins.

The eponymous Adel Rootstein, who founded the company in the late Fifties, died in 1992, but she is still around in spirit; there is an old black- and-white photograph of her in Southgate's office, showing a high-cheekboned, dark-haired beauty. And, he says, the firm has tried to remain true to her principles: constant innovation and high quality. Southgate, now 66, joined the company full-time more than 20 years ago, and he had already worked with Adel, an old friend, as a freelance since 1959. (He had trained in prop-making at art school and also had a successful acting career.)

The company caused something of a shop-window revolution, he explains. "Mannequins all used to be very aristocratic-looking. But things changed in the Sixties. Designers like Ossie Clark and Mary Quant came to Adel saying their clothes looked ridiculous on these racehorses, and asked her to make mannequins related to the clothes." Adel kicked off with mannequins based on Patti Boyd and Twiggy, and never looked back. Today, the company sticks to the idea of basing all its ranges on real people, usually models or celebs, although one popular mannequin is based on a housewife from Germany whom Adel met at a party.

The modern ideal of an androgynous, slouching beauty is hard to capture. "At the moment, attitude is out," says Southgate. "In the late Eighties, models were very sophisticated, with lots of attitude - think Linda Evangelista and the supermodels. It is much easier to capture this [and he sashays a few steps with a supermodel prance] than this [he slouches sulkily]. The natural look is very difficult - a slightly artificial glamour is much easier to copy."

The living model will pose for a sculptor for four hours a day, three days a week, over three weeks. More famous (and expensive) beauties who are to be immortalised in fibreglass may have a stand-in - Joan Collins could hardly sit still for three hours, recalls Southgate. Sometimes, a bit of cheating goes on, if the model doesn't quite fit in with the look of the moment. Legs may be lengthened a tad, bosoms enlarged or reduced a smidge; and all imperfections miraculously disappear. "Mannequins are stylised images, not real people and no real girl is as beautiful as a mannequin," says Southgate firmly.

The sculptor starts off with a metal frame, like a skeleton, and adds clay, roughly at first then a thumbful at a time. The clay model is cast in plaster, smoothed, and then a fibreglass mould is made from the plaster original. Then mannequins can be made as required, each one put together from five, separate pieces of fibreglass, and all made to order. So, you could ask for a Karen Mulder with green eyes and long dark hair or a Susie Bick or Ute Lemper or Catherine Bailey or Dianne Brill with blue eyes or red curls or a crew cut.

Adel Rootstein figures travel widely; a consignment of blank-eyed and still bald beauties were waiting to be sent to Greece; others were bound to Hong Kong, Germany, the Philippines. Before heading off around the world, they will visit the wig salon and the make-up studio. "We never say factory," says Southgate, and it certainly doesn't feel like one. In the wig salon, the air is thick with spray and gel; as well as straightforward bobs and snips, the dressers are busy with towering confections of wild Medusa curls (big hair is still very chic in Arab countries, it seems). Outside the make-up studio, hundreds of masks on the wall show the templates for "house make-up", this season's preferred styles for regular clients such as Dorothy Perkins and Next. The most delicate operation is the addition of the mannequin's eyelashes.

The company may have reached the pinnacle of its field, but Southgate still hankers after the old days. "At the beginning, we were so different, so avant-garde, so new. Now we've been around so long, we're establishment," he says. "Now we're established at the top, it's not really an enviable position. It's much nicer to be the new, creative, exciting company."

Watching the mannequins progress from rough moulds to glossily finished figures is fascinating, yet there is an eerie feel to the ranks of sightless eyes and racks of smooth, hard, perfect, fibreglass limbs. Southgate says, however, that his dreams remain unhaunted. "If you are used to things you look at them in a different way - you don't notice them. My father was a grocer, and in the war he was pushed by the Ministry of Food into becoming a butcher. He was literally green for weeks, he couldn't look at a piece of meat. But I grew up playing in slaughterhouses - there used to be piles of sheepskins, fresh off the sheep and quite revolting, but my friends and I would run around quite happily in them pretending to be sheep.

"I can see how it might all look a little strange to someone visiting for the first time, because presentation can completely change a concept. There was one occasion when I went into an art gallery where there was a butchers' counter, all laid out with trays with parsley in between them, and all the parts were human - there was a tray of breasts, a tray of toes. Now that shocked me completely."