It's a simple waistcoat, shirt and jeans combo for a fresh-faced Alexa, way back when.

This was a very glamorous dress, but a far cry from the former model's sleek signature style as we know it today.

Va va voom.

This Luella prom dress was an iconic fashion moment for the then-emerging style icon.

It was Luella again at the 2009 Baftas - this time in the form of an edgy floral mini dress.

Teamed with jet black tights and "school shoes" - it's a combination she's still keen on today.

 A buttoned-up shirt paired with a mini skirt, bare legs and Mary Janes - signature Chung.

A timeless LRD dressed down with chunky ankle boots, layered necklaces and, of course, messy hair.

A trusty Burberry trench is one of Alexa's signature looks.

Looking sharp in a Phillip Lim tuxedo to the Met Ball.

Yes, those are leather shorts.

What we like most about this audacious look is that she slung a cosy cardigan over her shoulders to finish it off - and got away with it.

We adore this Carven contrast-collar cotton shirt.

Fashion editors swooned over this vintage Balenciaga dress from Atelier-Mayer.

Chung made a sold case for denim prairie dresses.

Chung showed off her emerging style credentials in a beautiful Stella McCartney trouser suit and pointy-toed heels.

The Burberry trench took a break in 2012 when Chung fell for this soft mink-coloured coat and wore it to just about every show at London Fashion Week.

Chung was a vamp and a half in this black frilly-edged Moschino dress topped off with glossy red lips.

Chung opted for a girly and gorgeous vibe in Chanel Resort 2013, teamed with small sparkly earrings to keep the focus on this intricate ivory dress.

The model put her own stamp on this Thakoon runway look, pairing it with pillarbox-red lips and matching Mary Janes.

The moment when Chung made us all want a dungaree playsuit.

This summery yellow Valentino dress paired with silver courts, red lips and a swept-up 'do was show-stopping at the Grammys.

Chung did Chanel proud at the fashion house's Tribeca Film Festival.

And it was an ultra-sophisticated Chanel couture number and trademark red lips for her 30th birthday celebrations.

She rocked the boat in a peek-a-boo Erdem gown at the Met Gala.

Prim on the top half, party on the bottom half - quintessential Alexa Chung.

It's another work-of-art white dress. This time Chung toughened up a strapless Stella McCartney mini with a monochrome houndstooth clutch and strappy Mary Janes.

She looked ready to take off in this divine butterfly-print Valentino cape dress.

This was an uncharacteristic evening gown for the style icon, who opted to hit the red carpet in pastel blue Nina Ricci.

There was a lot going on with this outfit at the Royal Academy Summer Exhibition in June, but miraculously, she made it work.

Chung showed us all how summer dressing should be done in this pretty Carven dress.

The former TV presenter stayed cool and stylish in a daisy-print cold shoulder dress by US boho brand Free People.

She even managed to make floral look a little dangerous in this midi dress teamed, of course, with messy hair and shades.

Adopting a Miss Marple vibe at the polo.

A departure from her signature style in pastel pink Emilia Wickstead.

She made this Dennis The Menace style jumper desirable at London Fashion Week.

It was a preppy Marc Jacobs number for a winter event in New York.

Looking elegant in Emilia Wickstead at the British Fashion Awards.

Shades, skinnies and a huge shaggy coat - totally Alexa.

Yes! Dungarees and a killer shirt.

Chung launched her AG jeans collaboration in this £295 smock dress.

Who else could mismatch creams and look this good?

Slaying street style at London Fashion Week.

Rocking sixties-style in Louis Vuitton.

She made us want to buy a leather mac.

A thigh-split worn with attitude at the Christopher Kane London Fashion Week show.

Trying out wide-legged and slouchy in Chanel.

We'd happily get married in this Simone Rocha frock.

Secret pockets were sewn into her stunning Erdem dress at the Met Gala.

Edgy, in Christopher Kane.

Expertly modelling the Loretta playsuit from her AW collaboration with AG jeans - and check out those boots.

Keeping on the cosy side of stylish for London Fashion Week last February with this giant teddy bear coat.

Chung's signature red lip stopped this preppy in pink look from verging on twee.

Appropriately dressed for the Tarzan premiere in this wild velvet suit.

Chung sparkled in this Thakoon jumpsuit at the Met gala.

Dressed up in a leather Prabal Gurung number for the CFDA Fashion Awards.

The signature crimson lip was swapped for a deeper red to pop with this gold Prada strapless gown.

A classic boho look topped off with a straw handbag to walk the streets of New York.