The black spaghetti-strap, cream-colored couture gown is from the brand's January 2005 collection.
Roberts was also wearing exclusive pieces from Atelier Swarovski's first fine jewelry collection in support of the RCGD cause.
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According to the official Red Carpet Green Dress website, Suzy Amis Cameron is an “actress, environmental advocate, educator and wife of director James Cameron,” who “works with internationally acclaimed designers each year to dress stars in ethical evening wear and jewelry for the Academy Awards.”
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The “Scream Queens” actress said in a statement: “Seeing Suzy's [Amis Cameron] passion for people, for fashion and for the environment is inspiring, and I am thrilled to be a part of it. Roberts said in a statement. I'm honored to partner with Red Carpet Green Dress and wear one of Giorgio Armani's vintage gowns. I'm equally thankful to not just bring an ethical fashion statement to the Oscars, but to generate productive conversation that affects positive change to the world around us.”
See more: Oscars 2017 Red Carpet Fashion