The Duchess of Cambridge wears cult fashion label Self Portrait as she attends the premiere of A Street Cat Named Bob

The Duchess of Cambridge has joined women up and down the country by adding a Self Portrait dress to her wardrobe.Tonight, The Duchess attended The Recovery Street Film Festival and the worldpremiere of A Street Cat Named Bob in support of the charity Action on Addiction, of which she is patron.

Despite being a chilly November evening in London, The Duchess looked fresh and summery in a full-length white dressby the cult contemporary label which has sky rocketed to success in recent years, with its dresses becoming a regular sight on the backs of guests at weddings and other special occasions.

Self Portrait"s founder and designer Han Chong was delighted to see The Duchess wearing one of his dresses."It"s a proud moment for me as designer to find Katein one of my designs!She"s such an elegant women and it"s a dream to see.She looks incredible!" he told The Telegraph.

The design chosen by Kate, who met film makers who had created works inspired by their experience of addiction,features a chunky guipure lacebodice- a signature Self Portrait detail- with a prim raised collar and long pleated white skirt with a thigh split.In fact, the look would work perfectly as a bridal dress in its own right.Although the exact style worn by The Duchess is from the Resort 2016 collection and is not currently available to purchase, a more seasonal version with a scarlett skirt is currently retailling on Self Portrait"s website for ??320.

As the fashion bloggers Go Fug Yourself pointed out, The Duchess"s Self Portrait outing comes just days after Paris Hilton wore exactly the same dress to the amFARinspiration gala in LA- an unlikely style match is ever there was one.

Of course, The Duchess- who was introduced to Bob the cat and his owner Jim Bowen at the premiere-styled her take on the look very differently, with her brunette hair glossily blow dried and carrying aburgundy clutch bag and heels in contrast to Hilton"s bling-tastic tiara and white stilettos.

Self Portrait is something of a fashion phenomenon, with most dresses hitting on the sweet spot price point around ??300 which is within reach of many women but still feels like a special investment.???Our handwriting is glamorous, but it???s not totally full-on and over-the-top.It???s got an edge to it; a unique quirk.It???s not a conventional red carpet dress,??? founder Han Chong told Business of Fashion last year when the label was at the height of its growth, selling over 100 pieces each week in Selfridges and acquiring more than 250 stockists globally, an astonishing number for such a recently-founded business.

Although actresses, musicians, It girls and royals like The Duchess have access to gowns worth tentimes as much as Self Portrait, the brand has nevertheless proved a hit amongst many famous women.Kristen Stewart, Beyonce, Reese Witherspoon and Madonna are just a few of those who have chosen Chong"s feminine pieces.

Even Michelle Obama has cottoned on to the appeal of the label"s flattering cuts.The First Lady recently commissioned a custom-made design which she wore to give a speech at the UN General Assembly in September."Very emotional!First Lady of the United States@michelleobamain a custom made@mrselfportraitdress yesterday.An honour to dress a woman that we admire and respect so much," Chong wrote on Instagram at the time.

Now that The Duchess of Cambridge has stepped out in Self Portrait, the juggernaut shows no sign of slowing.

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