They were preparing for the 57th annual Miss Universe competition, which will be broadcast to millions of viewers across the globe on Monday.
Like her 84 million compatriots, Vietnam's 20-year-old contestant is hoping the show will let the world know about the new Vietnam, where commerce and fashion are thriving and war has become a fading memory.
"I want to introduce my country and my culture and our history to everybody," said Nguyen Thuy Lam, whose traditional costume is a Vietnamese ao dai, a colorful silk pantsuit. "I feel very confident when I wear the ao dai. I wish everyone would wear it and feel confident too."
The contest is being held in Nha Trang, a seaside city located next to a major American air base during the Vietnam War, which ended in 1975.
Given the history of hostilities between the two nations, Miss USA Crystle Stewart has been impressed by the warmth of her Vietnamese hosts.
"The USA and Vietnam are working together, in cooperation and peace," said Stewart, a Texan who is writing a motivational book. "Hopefully we'll be role models for other countries."
The show will be co-hosted by British pop singer Mel B, known as "Scary Spice" during her days with the Spice Girls. She will be joined by American television personality Jerry Springer, host of "America's Got Talent" and a long-running tabloid talk show that often climaxes with angry guests cussing and brawling with one another.
Springer is clearly enjoying his new Miss Universe job.
"Whoa!" Springer said during an interview with The Associated Press on Saturday, as dozens of contestants strutted across the stage during a rehearsal. "This is a plum assignment."
The 80 contestants have been in Vietnam for nearly four weeks now, receiving intense coverage from the Vietnamese media as they met with local dignitaries, frolicked in their bikinis and participated in various charity events.
They were hard at work Saturday preparing for the show.
Miss Serbia, 21-year-old Bojana Boric, is eager to compete in the swimsuit competition.
"It's a very good feeling," said Boric, who enjoys modeling, cooking and extreme sports. "It's your moment. It's the moment when everyone will see your face, and everyone will remember."
Beauty pageants have been derided by many as exploitative of women, celebrating superficiality over substance. Sweden's 2007 contestant dropped out after coming under pressure from pageant critics in her homeland, and the country is not sending a delegate this year.
But beauty contests are extremely popular in Vietnam, which is also hoping to host the 2010 Miss World competition.
After years of war and poverty, the country has been booming economically, and high-end cosmetics and fashion stores have sprouted up in Hanoi, the capital, and in Ho Chi Minh City, the country's southern business hub.
"It's great to have the Miss Universe competition here in Vietnam," said 18-year-old high school student Nguyen Thi Kieu My. "It will help to promote Vietnam's image in the world and bring in more tourists."