Nicole Richie in a navy three-piece look

Oh Nicole, do you ever get it wrong?

Rex Features

Leaving her Simple Life days well and truly behind her, Nicole Richie has gone on to become one of the coolest-dressed gals in celebsville, taking on practically every tricky trend out there and winning every time.

She's so sartorially savvy that wherever she goes we usually follow - her blue hair being one of the only exceptions that initially springs to mind. However, her most recent foray into the blue has us completely swooning... 

We clocked the 33-year-old starlet and mum-of-two leaving her hotel in New York City rocking a very sleek navy ensemble that we're dying to try for ourselves. Proving that suiting isn't just office-worthy attire, Nicole looked every inch the style maven in a midnight blue blazer complete with coordinating trousers and a matching roll neck top. Beaut. 

Finishing off her get-up with edgy velvet heels in burgundy and an on-trend gold chain necklace, Nicole's look was as slick as her glossed-back 'do. 

However, she wasn't the only noteworthy starlet to show off a navy three-piece this week... 

Actress Shailene Woodley of The Fault In Our Stars fame opted for a very similar guise while she was also in New York attending the screening of her upcoming flick, White Bird in a Blizzard. 

Mirroring Nicole's style, Shailene chose a navy blazer and trouser combo for the event but upped the tailoring ante up a notch by also working a fitted waistcoat to boot. Steering clear of all things glam, the 22-year-old beauty gave her ensemble even more of an offbeat spin by pairing it with chunky patent loafers and a wide jersey hairband. Nice work, lady.

So, if there's one thing you NEED to buy this week, it looks like the navy three-piece is officially it. Who are we to dispute? To the shops it is. Here's how we'll be getting in on the navy action...

Navy Lapel Blazer, £59.99, Zara
Some things just never go out of style and the navy blazer is definitely one of them; buy this tailored version and we promise you'll never tire of it. When you're not working your navy three-piece, try working it with skinny ripped jeans and clumpy heels for instant cool. 

Navy Wool Roll Neck Jumper, £29, John Lewis
Roll necks have been given a major seal of approval by the fash pack this season so you cab guarantee they'll be all over the high street come time. Get in on the trend early with this super-soft number from JL. 

Navy Tuxedo Trousers, £225, MM6 Maison Martin Margiela At Net-A-Porter
The black panels on these sleek trousers make the classic cut way more interesting. We recommend wearing them with a navy cami and black leather courts for your next night out. 

Continued below...

By Maxine Eggenberger 
Tweet me at @MaxFashWriter