The House actress looks absolutely stunning while posing up a storm in the promo shots, wearing items from the retailer's new range which is set to launch in selected stores on 16 April 2015 (which is ages away - boo!).
The Conscious Exclusive collection focuses on sustainable fashion, with garments made from more earth-friendly materials including organic silk, organic cotton and recycled polyester.
One photo sees Olivia sporting a sophisticated black halterneck jumpsuit complete with a plunging neckline, with her brunette locks styled in a straight yet slightly messy 'do.
In another snap, the mother-of-one wears a stunning feather print low-cut dress boasting a full skirt, accessorised with a pair of statement silver earrings.
We're seriously loving her make-up in the shots too, with Olivia sporting a sweep of warm-toned bronzer on her cheeks for an earthy look, teamed with a dab of highlight to give a dewy finish.
Her eyes were subtly defined with brown smoky eyeshadow and her lashes were layered with sooty black mascara, while her pout was kept an understated nude hue.
Olivia follows in the footsteps of pop royalty Beyoncé and supermodel Gisele Bündchen, who have both previously modelled for the brand, and Lady Gaga and Tony Bennett, who are the faces of H&M's current Christmas campaign.
Talking about her new role, Olivia said: "Sustainability is one of my biggest passions. I'm proud to be the face of H&M Conscious Exclusive, a collection which shows the stylishness of sustainability."
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