Ao Dai – a traditional costume of Vietnamese people is known around the world. Formerly, the Ao Dai was once the daily clothing for woman before the 1970s. Today, we see the image of ao dai everywhere: schoolgirls wear it as a school unifrom, teachers on the podium, many big companies dress their staff in it, and it has become popular at fashion shows, representing national costumes in international beauty contests. The Ao Dai is not only discreet, but also flatters the willowy beauty of Vietnamese woman.