As some of the biggest names in fashion prepare to show off their collections at London Fashion Week (LFW) over the next few days, a less mainstream area of fashion is also looking to make a statement on the catwalk.
Sustainable fashion – garments that are ethically sourced and produced – has been growing in popularity over the past few years, and is set to feature heavily in this year's LFW. In 2005 less than 5 percent of designers at LFW were sustainable fashion brands, but at this February's fashion show, almost a third of designers were eco-focused.
The spring/summer 2014 show, which kicked off on Friday, will feature ethical designers such as Katrien Van Hecke and Liora Lassalle, along with well-known sustainable designer Christopher Raeburn.
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"Designers are now getting it right. There is a big change from five or ten years ago when clothes weren't sustainable and were horrible," Willie Walters, course director of BA Fashion at the prestigious Central Saint Martins fashion school, told CNBC.
"From the point of view of designing clothes it is important that they are sustainably produced and are fashionable – and they have to be something that people want to wear."
Far from a being fad, industry experts argued that the eco-fashion industry is now on track for long-term growth, and the numbers certainly point to a booming industry. According to the Ethical Consumer Markets Report 2012, the industry was worth £150 million ($237.5 million) in 2011 - a tiny fraction of the £21 billion value of the whole British fashion industry, but a colossal jump from its £5 million value in 2000.
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The sustainable fashion industry does, however, face some significant challenges. In particular, the prominence of low-cost - or so-called "throw-away" - fashion has caused some consumers to expect an extremely low price for clothes - something that ethical fashion cannot deliver.
"Consumers expect to be able to get jeans for less than £5 ($8)," Tamsin Lejeune, managing director of the Ethical Fashion Forum, told CNBC. "In fact, if you were to produce the jeans and consider the environment along the supply chain you wouldn't be able to sell them for £5."
But industry experts are confident the sustainable fashion industry can overcome these hurdles. Creating memorable brands will be crucial to achieving this, according to Mike Schragger, the executive director at the Sustainable Fashion Academy in Sweden.
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"The fashion experience can't disappear even though you have a more ethical or sustainable product," Schragger told CNBC. "We know that consumers don't get excited about products or services that are more ethical but don't perform as well… So the branding of a product or company, and its relation to sustainability, is very important."
Eco-fashion will come of age when its designers do, designer Orsola de Castro, founder of green fashion brand From Somewhere, told CNBC. Sustainable clothing is in its "early days" because eco-designers in countries with strong fashion industries are still young, she said.
"Once the American talent become established designers, they will demand their production companies to work in a sustainable way," she said. "In places such as Hong Kong, fashion students are taking sustainability seriously and when they start penetrating the supply chain we will see some concrete changes."
—By CNBC's Arjun Kharpal: Follow him on Twitter @ArjunKharpal