The ao dai (áo dài) is a Vietnamese national costume primarily for women. In its current form, it is a tight-fitting silk tunic worn over pantaloons.
The ao dai is now standard for weddings, for celebrating Tết and for other formal occasions. A plain white ao dai is a common high school school uniform in the South. Companies often require their female staff to wear uniforms that include the ao dai, so flight attendants, receptionists, restaurant staff, and hotel workers in Vietnam may be seen wearing it.
Although the dress covers the entire body, it is thought to be provocative, especially when it is made of thin fabric. "The ao dai covers everything, but hides nothing," according to one saying. The dress must be individually fitted and usually requires several weeks for a tailor to complete. An ao dai costs about $200 in the U.S. and about $40 in Vietnam.