The 'Disco Love' singer proved her impressive style credentials as she pulled a sultry pose for the cameras, before heading into the charity fundraiser.
The star-studded event was co-organised by Eva Longoria, with proceeds going to charities including the Eva Longoria Foundation, Children In Need and victims of the Philippines typhoon Haiyan.
Keen to show her support, Vanessa - who recently took to the phones for the Philippines Appeal Telethon - oozed effortless chic while sashaying down the red carpet.
The songstress opted for a sexy black gown by Badgley Mischka from Girl Meets Dress, which featured a classy train and a peplum detail around the waist.
She kept the rest of her look simple, shunning the jewellery while slicking her nails a metallic berry shade.
The starlet wore her chestnut brown tresses in a side parting, tonging the lengths into voluminous, bouncy curls.
Beauty-wise she made her eyes the main focus of her look, blending smoky brown hues over her lids while donning low-key nude lippy.
Also attending the event was Eva's pal Victoria Beckham, Pixie Lott (whose boyfriend hosted the do) and Nicole Scherzinger, who looked schmazing (sorry, we had to!) in a silky silver gown.
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