The model worked a very busty blonde look as she arrived at London's Sketch nightclub in a plunging v-neck black dress.
The daughter of rocker Rod Stewart famously had her breast implants removed, so her ample - if a little uneven - cleavage is likely thanks to a push-up bra.
Taking the plunge: Kimberly Stewart the launch of a Playboy store last night
Playing up: the model worked the camera in an all black outfit
Kimberly had an enlargement at 18, but decided to return to her natural state - and rather curiously gave the lumps of silicone to her friend Jack Osbourne as a gift.
She said: "I gave him my implants, I framed them and I signed them and I engraved them and he has them on his bathroom wall.
Hello boys! Even Kimberly looks rather surprised at her buxom look
At the time, Rod encouraged her decision to take them out. She recalls: "He's very supportive of whatever I do. He was just like, 'If you don't feel comfortable, if you don't feel safe, just get them removed.'"
Meanwhile, a host of other guests arrived ready for fun at the Playboy store launch event, including reality TV star Danielle Lloyd, model Leah Wood and singer Lily Allen.
In his element: Calum Best was all smiles as he posed with Playboy bunnies
Bag ladies: Danielle Lloyd and Jade Goody enjoyed the free delights
Jade Goody, who's home was robbed earlier this week, also made an appearance but left swiftly after her ex Jack Tweed arrived.
Lothario Calum Best looked more than thrilled at his invitation and looked in his element as he posed up with a group of bunnies.
