This is the second glittering look the Sex And The City star has unveiled in as many days. Earlier this week, SJP stole the limelight at the world premiere of new stage musical Charlie & The Chocolate Factory at London's Theatre Royal Drury Lane.
Sarah, 48, attended last night's Serpentine party with hubby Matthew Broderick, and gave supermodels Kate Moss and Naomi Campbell - who both opted for plain black - a run for their money.
The star showed off her fabulous shape in the figure-skimming frock, and wore her long hair down with a simple centre-parting, letting it flow over her shoulders.
Ahead of father Mick Jagger's appearance with The Rolling Stones at Glastonbury this weekend, Georgia May Jagger showed off the famous Jagger pout with a slick of eye-catching red lipstick, perfectly colour-matched to her sequinned strappy red dress, and accessorised with a pair of silver sandals.
Another famous rock star's daughter, Pixie Geldof, flaunted her model-like pins in a micro-mini printed shift dress, accessorised with pointed red pumps and a sky-blue manicure.
And TV presenter, Zara Martin struck a monochrome note in a high-necked black jumpsuit with a ruffled white collar, and strappy black platform sandals.
Who do you think looked best? Let us know who gets your vote below!