There are no celebrities in the studios of Spanish fashion chain Zara, just hundreds of twenty-something designers copying catwalk lines faster than their labels can sell them.

While shoppers storm the stores of rival H&M for clothes designed by Madonna and Kylie Minogue, Zara has hitherto shunned the global craze for celebrity-designed, celebrity look-alike fashion.

As Britain's Top Shop buys wall-to-wall publicity for its popular Kate Moss collection, Zara sees no need for high-profile advertising.

Even its executives shun publicity, agreeing to be interviewed on a recent visit on condition they are not named.

It's all about speed, says one, looking out from a boardroom at a distribution centre the size of an airport terminal at their headquarters in Arteixo, northwestern Spain. Celebrities may work for other brands, not for us.

Some analysts applaud the formula: Luca Solca of the Bernstein consultancy says stars are a substitute for design, speed and quality. He compares firms that use them to athletes forced to take steroids to compete.

Trendspotter Marian Salzman of the JWT advertising agency in New York agrees: Zara is right to stay away from celebrities. It doesn't mean it's always going to be that way, she said.

Indeed, analysts say, it was Zara's fast-to-market model and H&M's hip, cheap lines that obliterated the European middle-market and forced competitors to sign up celebrities to compete.

But retail professor Andrew Newman says Zara could begin to slow as it tries to sell the same fashions across 64 countries and still make the majority of clothes in Europe.

In just over a decade, Zara's parent company Inditex has become world's second-biggest selling fashion retailer after Gap Inc. Zara drives two-thirds of sales.

With 8 brands, ranging from higher-end Massimo Dutti to Bershka teenwear, Inditex is opening more than a store a day as it targets fashion-hungry Europeans and China's middle class.

A classic problem with firms that have been successful is arrogance. It's possible that could happen to Zara, said Newman of Manchester Business School, England.

ZARA SECRETS

It takes up to a year for fashion houses to launch a catwalk collection but Zara can sell expensive-looking, affordable copies of the hottest trends within weeks of their debut.

Zara's limited lines appeal to shoppers who buy luxury look-alike clothes and mix high and low fashion, to keep people guessing if they are wearing Zara or designer label Marni.

Ask about Zara's answer to celebrities and, after swearing not to reveal the designs, journalists are taken to a basement studio where dimly-lit mannequins wear this winter's collection in elegant, minimalist window displays.

This is our catwalk, this is our marketing, says an Inditex spokesman.

Over the road in a vast warehouse, workers use bikes to navigate between miles of automated rails that ship 60,000 garments an hour to Zara stores and restock them twice a week.

Proximity of these logistic hubs to designers and factories in Europe means Zara can keep its cutting edge speed, rather than lose it, the spokesman explains.

Competitors make clothes in Asia to cut costs but take longer to get clothes to market or halt lines that flop.

CELEB PERILS

Analysts are still concerned Inditex has no plans to build logistics hubs outside Spain -- which no longer provides the majority of sales -- or to increase production in Asia.

Some say Amancio Ortega, Inditex's 71-year-old owner, has to delegate more control for Zara to keep its cutting edge.

He eschews celebrity tie-ins and opposes online sales.

His youngest daughter Marta, 23, begins work at Inditex this year and may join a budding second generation of managers.

Salzman says they will have to deal with Zara stores that are growing a bit chaotic and need more staff after two years of cost controls. She fears the label may be settling into being attractive to the middle-aged rather than attracting a new generation.

At some point, they may have to commission stars if that is what customers want, says Salzman in New York.

Among the perils of using celebrities, say analysts, is the fact authentic stars are hard to find and members of the glitterati can become publicity accidents.

U.S. brand Jill Stuart commissioned singer Lindsay Lohan this year only to see her arrested for drunk-driving and check into rehab.

But British mass-market brand New Look sees no end to shoppers wanting to dress like celebs and has signed singer Lily Allen.

In Spain, source of around 40 percent of Inditex sales, actress Milla Jovovich has boosted sales for Barcelona fashion house Mango. Penelope Cruz will add panache to their next collection.

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