The blonde beauty was joined by an A-list line-up - including actor James Franco - at the BMW i3 event
Sienna Miller set the style bar high as she rocked pretty prints to join a star-studded line-up at the BMW i3 global bash in London last night.
PICS: SIENNA MILLER AND TOM STURRIDGE GET INTIMATE FOR BURBERRY CAMPAIGN
Fresh from an Italian getaway with boyfriend Tom Sturridge, the blonde beauty showed off a golden glow as she arrived for the big reveal, held at Old Billingsgate market.
Holding a masterclass in summer styling, Sienna chose a pretty, printed Dolce & Gabbana dress, teamed with delicate Charlotte Olympia heels, statement earrings and a pretty pink lip.
Love.
The actress was joined at the launch by Hollywood hot star James Franco, who sizzled in a Gucci suit, while Donna Air (sans James Middleton), Laura Bailey, Amber Le Bon and Poppy Delevingne were all in attendance.
Speaking at the launch, where she had the chance to try out the environmentally friendly new car, Sienna Miller said: 'Being a new mother I feel it's very important to make green choices and create a better world for the future.'
Jumping inside, she giggled: 'It's the perfect city car. Ooh double doors!'
Meanwhile James Franco said he could see himself driving one in Hollywood. 'Going green is now cool. I'm really excited about this, it's about time we started taking care of the environment. It's fantastic. I feel like it's the future,' he said.
'I'm happy to be involved with something that's green. That's cool. I like the orange one and I think it will cope with the Hollywood Hills just fine.'
We think so, too.
WATCH: Stars hit BMW launch...
What do you think of Sienna Miller's latest red carpet look? Let us know in the comments box below…
PICS: SIENNA MILLER AND TOM STURRIDGE GET INTIMATE FOR BURBERRY CAMPAIGN
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