Mary-Kate Olsen rocks a black leather Givenchy jacket with studded sleeves while shopping during Paris Fashion Week on Friday.

Mary-Kate and twin sister Ashley also visited the Bourdelle Museum in Paris and sat front row at Chanel’s Ready-to-wear Autumn/Winter 2008 fashion show at the Grand Palais.

WOULD YOU WEAR Mary-Kate’s studded-sleeved jacket?

15+ pictures inside of Mary-Kate’s studded sleeves… More Here! »

Mary-Kate Olsen rocks out head-to-toe black at the Giambattista Valli Fall/Winter 2008/2009 Collection held as part of Paris Fashion Week in Paris, France on Thursday.

It was recently announced that Mary-Kate and twin sister Ashley, 21, are working on a coffee-table book about fashion, titled “Influence.”

“Mary-Kate and I have filled ‘Influence‘ with the most interesting, challenging, creative people we know — the ones who helped pave the way for us and our generation,” Ashley said in a statement.

“Ashley and I interviewed the people who have inspired us, with the hope that they will inspire and teach others,” MK said in a statement.

The Victoria Shoe by Giambattista Valli (as inspired by Victoria Beckham); shades by Chanel (Spring 2007, S5018 Black and Gradient Grey); and dress by Valli.

Just how twisted are twin sisters Mary-Kate and Ashley Olsen?

The latest issue of Star digs deep into the weird world of the billion-dollar twins. Apparently their bodyguard spoke out on the twisted sisters and surprisingly, MK&A have BAD BREATH and DIRTY HAIR!!!!!

Who wudda thunk it?

Mary-Kate Olsen speaks out days after the the death of Heath Ledger.

“Heath was a friend,” MK tells ET. “His death is a tragic loss. My thoughts are with his family during this very difficult time.”

Mary-Kate Olsen and Heath Ledger were dating for three months before Heath’s death, reports People.

Ledger, 28, and Mary-Kate, 21, first met summer 2006, when he was living at Hollywood’s Chateau Marmont.

“Mary-Kate and Heath were casually dating for three months before Heath’s death,” a source reveals. “They were hooking up, but neither were particularly interested in making it exclusive… They had a bond that was based on partying, and they had the same tastes in partying … like, in terms of where they liked to hang out in New York, what time they would want to go out. They just had the same sensibility.”

Earlier this week, New York Post and Daily News reported that the two were dating.

Mary-Kate Olsen arrives at the premiere of The Wackness on Friday held at the Racquet Club Theatre during the 2008 Sundance Film Festival in Park City, Utah.

MK told the audience that filming her makeout session with costar Ben Kingsley was ”fun” — even though she was worried the whole time about accidentally removing his hairpiece.

That might make things slightly awkward!

20+ pictures of Mary-Kate and her Wackness co-stars… More Here! »

Mary-Kate Olsen squeezes in some last-minute holiday shopping, spending about five hours at the designer vintage store Cat Walk in West Hollywood on Saturday.

The 21-year-old petite actress left the second-hand designer heaven loaded with gift boxes galore and had an assistant carry out bags full of gifts as well!

It’s been reported earlier this month that MK is seeing Brothers and Sisters Dave Annable. The pair was first spotted at at Chateau Marmont Hotel’s restaurant on early December, where they reportedly dined with a group of friends including Nicole Richie.

Mary-Kate Olsen has been hospitalized with a kidney infection!

The 21-year-old actress was admitted to the emergency room of a New York hospital on Monday.

“Mary Kate got a kidney infection,” says rep Nicole Caruso. “She’s resting comfortably and will be released in the next day or so.”

Get well soon, MK!