This year, though, she shared the best dressed title with Geri Halliwell, who caused a flurry of excitement as she left from George Michael's house for the party.
Former Spice Girl Geri, was on radiant form in a fairytale-style creation, featuring crystal beading at the bust and with her strawberry blonde locks styled into a cascade of ringlets.
Outside the gates of the Candle In The Wind singer's Windsor home, a who's who of the celebrity world were seen pulling up in the finery.
Lily Allen had opted for a delicate metallic lace dresss, set off by a chic platinum wig. Also on the glitzy guest list was newlywed Samantha Janus and husband Mark Womack, along with Kelly Osbourne, Sophie Ellis Bextor and Lily Cole.
Representing the veteran showbiz crowd were Lulu and Shirley Bassey. The Welsh diva shared a giggle with her fans, holding up her manicured hands eagerly to show a deep shade of varnish that matched her royal purple frock.