Not all shoppers are the same. Some women love to trawl the high street on the off chance that something might catch their eye. Others approach shopping with the strategic skill of a three-star general: the internet is her weapon and she has her personal shopper on speed dial. She’s a shopzilla, and she’s already bought most of her autumn/winter wardrobe.

Shopzillas shouldn’t be confused with spendaholics. A shopzilla would never buy for the sake of it. She plans ahead, does her research and makes informed decisions. For Fiona White, who runs her own events company and is the executive producer of Glasgow’s famous T in the Park event, adopting these tactics is the only way to fit getting dressed into her hectic lifestyle. “My office isn’t near the boutiques and I often don’t have time to shop,” she says. She has developed a close relationship with the buyers at Cruise, Glasgow’s chic label boutique, and plans all her purchases with them. “I’m not slavishly into fashion, but I know what I like and what suits me. I don’t make the mistakes I used to,” she says. “I look online at style.com, then speak to the girls at Cruise. Next season, I’ve got a fantastic Burberry Prorsum double-breasted coat on order. It’s coming in August and Glasgow is cold, so I can wear it in September.”

White is just one of a growing number of fashion-savvy women passive into something completely proactive. “Customers are wise to websites such as vogue.co.uk and style.com, and in the desire to be seen in something first, they don’t think twice about calling up to put their name down for forthcoming collections,” says Averyl Oates at Harvey Nichols. “We have already had a number of inquiries about Moncler Gamme Rouge, designed by Giambattista Valli, from people who haven’t even seen the collection yet.” So keen are its customers to shop the catwalk, it has had a waiting lists since March for Valli’s plunge-fronted party frock and Christopher Kane’s 1920s-style party dress.

The story is the same at Browns and Matches, where customers are obsessing over next season’s moulded black cocktail dresses and costume jewellery from Balenciaga. At Harrods, shopzillas are racking up orders for Balmain gowns and Fendi bags studded with precious stones, and the store expects to sell out of Chanel by August.

Net-a-porter.com is at the forefront of the I-want-it-now culture. It offered customers the opportunity not just to pre-order from the autumn/winter Halston collection, but actually buy pieces straight from the catwalk. This prompted an online stampede, with more than 300,000 people viewing the collection, and the two items available for delivery (a belted Grecian dress and a sleek shirt dress) sold out within hours. “Our aim is to provide immediacy and access. It’s a very 21st-century approach,” says Holli Rogers, head of retail.

The shopzilla’s natural territory is the designer boutique, however, where customer service is at a premium, but there are Shopzillas on the high street too. After Banana Republic put its spring/summer fashion show online, the store saw a jump in customers preordering the one-shouldered pink silk dress and the giraffe-print patio dress. At Marks & Spencer, a pre-order service is available online for certain items; there is currently a growing waiting list for the chic cream tailored leather dress.

As more and more of us rely on the immediacy of the internet for fashion information and to shop, so the phenomenon of the super-savvy, super-demanding customer will grow. In a few years’ time, we’ll all be a nation of shopzillas. Are you ready for that?

HOT ON THE HIGH STREET

New Look: a fab festival dress, £35, hits the stores on May 20

Urban Outfitters: Alexa Chung is on the waiting list for their lilac dress, £175

M&S: a leather dress, £149, is available instore tomorrow

Celia Birtwell for Topshop: playsuit, £100, is from the new range and goes instore on July 30

Banana Republic: after customers saw a preview of their purple asymmetric dress, £95, on Banana Republic’s website, the waiting list began to grow

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