During the day, the famed stores along Fifth Avenue are filled with a cacophony of clacking stiletto heels, Muzak and chattering shoppers searching for the perfect frock. After-hours, however, it's been party time, Eighties-style, behind the sumptuous window displays. Wednesday night, for example, the social parade kicked off at Saks Fifth Avenue, where guests arriving to fete Rachel Roy were greeted by the bass line of Tone-Loc's "Wild Thing." Roy, radiant in burgundy hues and some serious Lorraine Schwartz diamonds, graciously greeted her friends and fans, smiling all the while for the countless cameras and cell phones. Nearby, the evening's hostess, Iman, gazed on with pride. "She's one hell of a designer," the model beamed.

Meanwhile, Roy's other half, Damon Dash, was busy encouraging some prim and proper guests out of their shells and onto the dance floor to "get down with O.P.P."

Further up the avenue, Versace held a bash with the Young Friends of Save Venice to preview its spring collection and Chloë Sevigny threw a party at Bergdorf Goodman for her pals Lazaro Hernandez and Jack McCollough of Proenza Schouler. The store's designer floor turned into a dimly lit den, where designer-cum-DJ du jour Ben Cho kept guests including Barbara Bush, Aerin Lauder, Tim and Helen Schifter, Amy Sacco, Hana Soukupova and Lauren Davis and Andrés Santo Domingo shouting over a mix of Top 40 hits of yesteryear.

But it turns out that even movie stars can't always get what they want. "I did buy some of their Target stuff," Sevigny revealed of her Schouler stash, "but to acquire more of the real thing I need to go to more sample sales."

Meanwhile, across the pond, it was the clink of jewels, not music, that got hearts pumping at a Ralph Lauren lunch in aid of the Serpentine Gallery's arts education program.

"I knew I couldn't compete with all the diamond engagement rings in the room — so I brought my own!" joked Eloise Anson, showing off her costume jewelry set with mirrors the size of 50 pence coins. "It's the Elizabeth Taylor effect."