It has been described as “the most innovative and devastating retailer in the world” by its peers, and now it has taken the crown as the globe’s leading fashion retailer.

Zara. The fashion retailer’s name conjures up admiration and envy among high street rivals.

“Genius. What the fashion industry is all about,” said Green in an interview with Retail Week (April 11). Rare praise indeed.

So how has parent company Inditex – which began in 1963 when reclusive founder Amancio Ortega produced bathrobes from his bedroom in northwest Spain – overtaken US giant Gap with worldwide sales of €2.2 billion to Gap’s €2.17 billion (£1.75 billion to£1.73 billion)?

Since its first store opening in A Coruña in 1975, Zara's armada has moved at a rate of knots to become a chain that today has nearly 3,900 stores in 70 countries.

At the same time, Gap, once beloved for its classic basics and preppy style, has been becalmed and is facing the prospect of further choppy waters.

In the same week that its crown slipped, Gap revealed it was axing its London-based European design team, the very thing that Gap followers hoped would raise it out of the doldrums.

Gap’s reasoning that customers want more US-style clothing does not add up. Less than a year and a half ago a failure to capitalise on European shoppers’ desire for edgier Euro chic fashion led to the creation of the very team that has been chopped.

Meanwhile, Zara’s uniquely successful vertical integration model has allowed it to deliver fast fashion with a high fashion edge.

Its Spanish in-house design team, which oversees product from conception to the rail, is able to translate the latest catwalk trends in to stores at record speeds.

If something does not sell within a week, it is pulled and some 10,000 designs pass through its doors in a year.

Gap’s basics feel basic by comparison. And Zara achieves success in spite of spending very little on marketing. Or should that be because of? Its stores are all the advertising it needs. Unlike Gap and many other high street retailers, Zara has managed to project a boutique feel on a global scale.

While Zara has innovated Gap has stagnated.

The test for Inditex will be whether it can emulate Zara’s success with its other emergent brands such as Massimo Dutti, Bershka and Pull and Bear.

The test for Gap too is whether it, along with its Banana Republic brand, which is closer in feel to that of Zara, can close the gap on its rival again.

So far, so fast, so good for Zara.