The French actress wore a Dior couture gown. Cotillard is a friend of the house, and has been "Lady Dior" since 2008. The historic Parisian fashion house seems keen to dressing her for red carpet events.
The glowing, pregnant British actress wore a tulle-embroidered gown with flowers by Valentino Couture dress from the spring/summer 2015 collection.
The Best Actress winner wore a custom-made Chanel couture gown by Karl Lagerfeld, exclaiming on the red carpet "Karl made this for me." According to her stylist, the gown was made by 27 people, and took 965 hours of work.
The blonde had another pretty in pink Oscars moment in a custom-made pale pink silk-crepe Ralph & Russo couture gown, featuring a shoulder rosette of delicate oversized petals in gazar and organza. This up-and-coming design duo Tamara Ralph & Michael Russo has been placed on Vogue's "Ones to Watch in 2015" list.
The American actress wore a Givenchy gown by Riccardo Tisci. This custom-made outfit is standard for Chastain's red carpet appearances as she is a friend of the house who regularily dons couture from Givenchy.
The Best Actress in a Leading Role nominee had a breakout year with blockbuster hit Gone Girl. She shone on the red carpet wearing a Givenchy Haute Couture by Riccardo Tisci.
South African super model and Victoria's Secret Angel wore an Armani Privé black bustier and full-length skirt. She attended the show with husband Adam Levine, frontman of Maroon 5.
As part of the cast of Birdman, the Oscar-winning Best Picture of 2015, Emma attended the awards in support of her cast and director Alejandro González Iñárritu, who also won Best Director. She wore a custom Elie Saab Haute Couture Spring Summer 2015 in chartreuse.
Versace had a knockout year on the red carpet, dressing over a dozen A-list celebrities, including the beautiful Zoe Saldana. The American actress is in a custom-made Atelier Versace blush gown draped at the waist, with a full train.
Shimmering in a fully beaded nude gown, Abiston flaunted a side slit when she wore Atelier Versace Spring 2015.
Making the attendees green with envy, Scarlett's custom-made Atelier Versace emerald green gown had a collar delicately embroidered with 2,000 Swarovski crystal stones.
Sports Illustrated swimsuit Chrissy Teigen model wore a cornflower blue long-sleeve beaded gown from the Zuhair Murad Spring 2015 Couture Collection.
Photos by Getty