From heirs to the throne to pop princesses, celebrities – especially royal ones – have a profound influence on fashion. From Grace Kelly’s ethereal gowns to Princess Diana’s fashion forward statements to the modern classics worn by Kate, the Duchess of Cambridge, we take inspiration from queens of style past and present.

Princess Grace of Monaco. Photo from Hollywood archives.

Their fashion choices can launch careers and send clothes flying off the racks the world over. The ‘Kate effect’ is said to be worth over £1 billion to the British fashion industry alone. Australian designer Carla Zampatti has commented that the Duchess is the best promotion for the fashion industry she can think of.

Indeed, over the past two weeks Australia was in the grips of royal fever as the Duke and Duchess of Cambridge where visiting the country as part of their first royal tour Down Under. Media frenzy set off by Prince George aside, all eyes were on the Duchess’s wardrobe.

From the wattle-coloured dress by Serbian designer Roksanda Ilincic to the Alexander McQueen blush pink and dove grey outfits, Kate reigned supreme during her many public appearances in Australia.

Zimmermann dress worn in Sydney, Australia by the Duchess of Cambridge. Photo credit: Samir Hussein/WireImage.com

She gave a nod to local designers, too, wearing a white eyelet dress by Zimmermann to the Manly Beach in Sydney, Australia and selecting a bright turquoise dress for her landing in New Zealand by Emilia Wickstead, one of her favourite designers.

Although the grass green outfit the Duchess wore to the official reception in the Parliament House was a stunner, we have yet to see Kate in a real glam-and-green outfit. In the words of award-winning ethical designer Henrietta Ludgate, the Duchess’s impact on sustainable fashion would be unprecedented.

Emerald green dress worn by the Duchess of Cambridge in Canberra, Australia. Photo: Reuters.

As Their Royal Highnesses were concluding their Australian tour, another royal lady with an Aussie connection, the Tasmanian-born Crown Princess Mary of Denmark, was hosting the 2014 Copenhagen Fashion Summit.

Billed as the world’s largest gathering on sustainability in fashion, the Summit took place on April 24^th, the first anniversary of the Rana Plaza disaster in Bangladesh. The event brought together the industry’s biggest players – from street giant H&M to the luxury group Kering – as well as the leading journalists and campaigners for a more sustainable fashion future.

Crown Princess Mary of Denmark speaking at the Copenhagen Fashion Summit. Photo: CFS.

In her opening speech, the Crown Princess of Denmark admitted that “Being 100% sustainable is very difficult to achieve”. Still, here’s to hoping that royals lead the way in shifting public opinion by declaring: “Fast fashion is dead. Long live sustainable fashion”.