Right now, it's safe to say that your Who What Wear editors' brains are about as busy as they get. We've got the official start of NYFW--and all the madness that entails--on our minds, not to mention we're dealing with deadlines galore and trying to remember that Valentine's Day is just around the corner too: yikes! Happily, all the excitement and stress around the office isn't getting in the way of our most important tasks: providing you, dear readers, with tons of excellent outfit ideas and identifications. So whether you have a hot date set up for Monday night, are looking forward to an upcoming GNO, or are planning on spending the week like us--immersed in shows--we've got all your sartorial quandaries covered. Just let today's What Was She Wearing: Answers! be your style guide and we'll gladly help you achieve the rest!

Mary-Kate and Ashley Olsen
The only thing better than one amazing Olsen outfit is two! You spotted the stylish pair in New York last week at a celebration for Textile Elizabeth and James and loved their looks, so we're more than happy to give you the inside scoop. Mary-Kate (left) showed up to the event in a refined combo, wearing a black vest by The Row, a Prada long-sleeve shirt, Textile Elizabeth and James pants, and Balenciaga heels. Ashley, on the other hand, opted for a more eccentric look, styling her olive green Textile Elizabeth and James trousers with a fox-emblazoned vintage sweater and mint green Balenciaga heels. Now, if it's MK's ensemble you're after, you only need a few basic pieces to get you started. We suggest trying National Jean Company's Vintage Havana Top ($68) with BDG's Hi-Rise Cigarette Jeans ($58) in Plum and Stella McCartney's Heels ($428). For those of you who'd like to put together an eye-catching outfit similar to Ashley's instead, definitely snag PJ by Peter Jensen's Dog Sweater ($60) and pair it with Urban Outfitters' Alexander Pants ($79) and River Island's Rexy Block Heeled Loafers ($108); the results will definitely be quirky, but in a good way, of course!

Nicky Hilton
It's not hard to see why so many of you adore Nicky Hilton's latest sartorial mix. The jewellery/handbag designer was snapped shopping in Los Angeles last week looking polished in a silky Tucker scarf blouse, J Brand's 926 Seven-Eighths Jeans ($158) in Ink, and gold Christian Louboutin heels. Additionally, you love that she gave her sweet outfit an extra pop of colour via a red Chanel bag. The resulting look is so simple and chic--perfect for a day at the office or a first date. So whether you have a day packed with meetings or a dinner with a new fellow on your schedule, try Topshop's Sophie Pussy Bow Blouse ($76) with Hilton's exact J Brand jeans and Pella Moda's West Open Toe Platform Pumps ($149). And if you want to give your look a vibrant finish a la Hilton, Lulu Guinness' Quilted Lips Leather Eyelet Anna Bag ($370) will certainly do the trick!

Anja Rubik
While it's always a good idea to look at your favourite celebrities for smart dressing ideas, it's just as intriguing to see how industry insiders are working the latest trends into their daily mix. Hence, your excitement about Anja Rubik's downtown-chic outfit! The gorgeous blonde was spotted out and about in Poland two weeks ago wearing a chocolate brown Rick Owens jacket with fur-collar trim, DKNY + Thomas' Pink White Cotton Fitted Tuxedo Shirt ($195, 800.231.0884), and a coveted pair of Isabel Marant cropped leather pants. Rubik completed her look with DKNY's Black Leather Ankle Strap Sandals ($335, 800.231.0884) and a Lanvin bag. To create a similarly cool outfit, start with Nasty Gal's Shearling Drape Jacket ($68) over a pair of leather skinnies, like Blank's Black Leather Crop Skinny Pants ($150). Then simply pick up Pelle Moda's Franky Platform Sandals ($180) and you'll be ready to hit the town.

Rachel Bilson
We are more than thrilled to see Rachel Bilson making her return to the big screen in Waiting Forever--the film debuted this past Friday--but rave reviews are also in order for the noteworthy ensemble she put together just last week. The style star opted for an edgier evening look for the Los Angeles premiere of said film with the help of a few fabulous Burberry Prorsum pieces--specially, a one-of-a-kind S/S 11 dress (sadly, not available for retail), Quilted Fitted Leather Jacket ($3594), and Studded Folding Leather Wallet ($525, 212.925.9300)--and Christian Louboutin platform pumps. As Bilson so aptly demonstrates, throwing a leather jacket over your feminine dress is an excellent and easy way to de-sweeten your whole ensemble. Simply style a girly frock like Nasty Gal's Frilled Skater Dress ($68) with ASOS' Collarless Quilted Leather Jacket ($215), and voila! You have an after-hours look that is wonderfully cool and chic.

Jessica Alba
One of the things we like best about Jessica Alba is that she knows how turn out an envious ensemble come rain or shine! Case in point: the heavenly pieces she was snapped wearing upon arrival at Charles de Gaulle Airport in Paris late last month. Our December Guest Editor wore a Veda jacket--the contrasting leather sleeves are an intriguing touch--and Balenciaga boots. To polish off her winter outfit, Alba selected her go-to bag of the season, Viktor & Rolf's The Just In Case Bag ($1095, 310.652.0200). If you're ready to emulate Alba's outfit, we suggest picking up IMPROVD's Convertible Leather & Knit Jacket ($658); it's sure to keep you toasty and stylish for the remaining winter months. And although Alba's Balenciaga boots are sadly no longer available, Pixie Market's Suede Buckle Boots ($92) are an excellent alternative you can pick up today! Just be sure to have Topshop's Black Frame Holdall Cross Body Bag ($80) on your arm, and we promise you'll turn heads a la Alba.--Jessica Baker

Photo of Mary Kate & Ashley Olsen, courtesy of Wire Image; Photo of Anja Rubik, courtesy of X17; Photo of Nicky Hilton, courtesy of INF; Photo of Jessica Alba, courtesy of Bauer Griffin; Photo of Rachel Bilson, courtesy of PCN