The celebrity-studded night lured shoppers into stores for celebrity spotting, music, giveaways, food and drinks, and, just maybe, shopping.
By early evening in New York, the basement beauty floor of Bergdorf Goodman was packed. Madeleine Russell of Manhattan, wearing her FNO shirt from last year, got her nails done ahead of a long line. She attends Fashion's Night Out events every year.
"I'm inspired by all the fashion around me and I get my own ideas," she said.
Like the FNO pro she is, Russell planned to head home from Bergdorf to put on makeup and her Manolo Blahniks to see Cyndi Lauper at the Blahnik store promoting her new musical, "Kinky Boots."
Across town, Kim Kardashian signed $123 gift sets of her perfume True Reflection at Lord & Taylor and was ready to hop a plane to Charlotte, N.C., for an after party for the Democratic National Convention.
"Because it is a lot of running around I wanted to be comfortable," she said. "This Tom Ford dress is, like, stretchy. So at least I'm really comfortable."
Fashion's Night Out - launched in 2009 in New York by Vogue editor-in-chief Anna Wintour - has proven so popular that it's now a fixture in some 19 countries, over three weeks involving tens of thousands of shoppers.
By dusk in Paris, the luxury shopping district was awash with thousands of people out to see spectacles like the one at Chloe, where a parade of dancing cheerleaders descended from a Chevrolet truck.
"There are too many people here to buy clothes. But people get to know the brands, and buy another time. Today, it's all about fun," said Corine Marneffe, 50.
In London, models Yasmin and Amber Le Bon (wife and daughter of Simon) were walking in a fashion show at the Westfield shopping center along with Lizzy Jagger (daughter of Mick).
But the splashiest events were in New York, where Donna Karan schmoozed with Miss Piggy at the DKNY store on Madison Avenue, the pig in a black dress designed by Karan herself - fittings and all. The two fashionistas posed together with hunky New York City firefighters featured in the fire department's calendar, their ladder truck parked outside.
Michael Kors helped judge a karaoke contest with Debra Messing and Sports Illustrated swimsuit cover girl Upton at his Madison Avenue store. He called Fashion's Night Out the trifecta: "It's starting the new season, you're excited to see what's in stores. You're reminded it's fun to shop and you can feel the energy."
At the nearby Ann Taylor store, bank worker Lenore Muller of Manhattan headed inside for a chance to be made over by stylist Mary Alice Stephenson and get counted among 50 women to pose in the store's windows for the crowds outside.
"We call it window glamming," Stephenson said.
At Bergdorf Goodman, crowds out to see Victoria Beckham, Rachel Zoe and Robert Verdi wore Burger King-style hats promoting the store. A glass bar in the Donna Karan department shattered and a kid ate ice cream - chocolate - dangerously close to the Pucci department. Nearby Bendel's was too crowded to enter later in the night.
Pharrell was at Bloomingdale's promoting his collaboration with designer Mark McNairy. "It makes sense as fashion has given so much to me for us to try and give back and support the movement for what these guys do," he said.
Not far away was "Twilight" star Kellan Lutz, supporting the bedding collection Charisma. Fortunately, bedding is instrumental to his style. "See, the good thing about being a guy, you get the whole bed-head look waking up," he said.
At the Macy's in Herald Square, 38-year-old customer service rep Keisha Carter from Brooklyn picked up two shirts and a dress on sale, but she admitted she hadn't realized it was Fashion's Night Out - for the second year in a row! She said she enjoyed the energy.
"People are more helpful," Carter said. "There's a busy-ness feeling, even more than usual."
In the makeup department, Lorrin Lynn, 24, a CPA, got a free makeover at Bobbi Brown after buying her special FNO lipstick. She also went hunting for reality star Bethenny Frankel showing off her shapewear line in the intimates department and "Bachelorette" star Emily Maynard at the Benefit Cosmetics counter.
"It's fun to go out to the stores, see the trends, and there's free booze!" said Lynne, cruising the night with a friend for their second FNO.
At Lord & Taylor, several hundred people lined up for Kardashian's autograph.
"Kim is the only person I put my life on pause for," said Aaron Ward, 26, a personal trainer from the Bronx who showed up at 4:30 p.m.
He bought the Kardashian perfume gift set for his mother and has purchased more than 50 other items from the Kardashian brand as gifts.
"I love Kim but I am not a girl," he added. "I am a Kim Kardashian curator."
Meanwhile, Nicole Richie and Jennifer Hudson were among a handful of designers who were promoting their creations on QVC from 9 pm to 12 midnight. "It's a dream to debut on Fashion's Night Out," said Jennifer Hudson, who had just finished a 12-minute segment selling 13 pieces of her new collection exclusive for the home shopping network.
This is the third year that QVC televised its shopping program in Manhattan on Fashion's Night Out. Company officials noted that viewership typically is twice what they see compared to other days.
Does all the starpower and hoopla help at the register? "Ask me tomorrow," Max Azria said with a laugh backstage before his BCBG presentation at New York Fashion Week. He said it can't hurt to meet shoppers.
Stores across the U.S. also held events, though less star-studded. In Chicago, Saks Fifth Avenue offered free cocktails, hors d'oeuvres and music; in Atlanta, Lenox Square Mall gave out gift bags and makeup touch ups at Aveda.
Models walked a quarter mile runway at the Galleria Dallas. The mall's fashion expert Holly Quartaro said that by the end of the night, each model will have walked a mile and a half in heels. NorthPark Center featured runway shows, beauty stations for mini-makeovers and an exhibit of Roberto Cavalli gowns.
"We've got an amazing crowd out here," said the shopping center's director of public relations, Victoria Snee, adding that some shoppers were "dressed to the nines."
Fashion's Night Out, timed for the first day of New York Fashion Week, also coincides with the final night of the Democratic National Convention. A Vogue spokeswoman said the event was planned a year in advance with thousands of retailers.
She added that Wintour is a supporter of President Barack Obama and noted that shoppers had five hours of events - plenty of time to get home to watch Obama speak if they wish.
Thakoon Panichgul - who has dressed first lady Michelle Obama - planned to do just that. But the conflict didn't bother Simon Doonan, the creative ambassador-at-large at Barneys: "That's what Tivo's for."
NBG Productions analyst Brian Sozzi said Fashion's Night Out started inconspicuously but has gained traction over the years.
"It gets customers into stores in a non-peak hour after work and it gets them energized," he said. "It's a win-win for retailers who are piggy backing on Fashion's Night Out's own marketing so it's not a big investment for them."
On Twitter, Fashion's Night Out's hashtag, (hash)FNO, was one of the top trending keywords. Laura Ashley tweeted about goodie bags while designer shoe label Christian Louboutin shared a special Fashion's Night Out Spotify playlist.
Kelly Talamas, director of Vogue Mexico & Latin America, said that last year's Fashion's Night Out boosted local sales. For its second year, Fashion's Night Out Mexico more than doubled the number of participating stores, to 250 from 100 in 2011. FNO Mexico will also expand to the Mexican city of Guadalajara, where activities will be held Sept. 13.
"Mexico is one of the strongest countries in the fashion scene, there is knowledge about fashion and interest in shopping," Talamas told the AP. "All the brands representatives told us that they sold a lot. There were some who said to us: 'Wow, we sold more than ever! This has been the most successful day in the year,'" she said.
Associated Press writers Mae Anderson, Anne D'Innocenzio, Nicole Evatt, Leanne Italie, Fay Abuelgasim and Karen Abbas contributed to this report from New York. Thomas Adamson contributed from Paris, Cassandra Vinograd contributed from London, Isaac Garrido from Mexico City and Jamie Stengle from Dallas.
Get Eyewitness News Delivered