This is a colorful Mexican Fiesta dress. They dresses are designed to be worn loose, comfortable and off the shoulders.

It is a two piece outfit with an elastic waist. The waist is 7 inches across, but can expand to about 16 inches across. So it can fit a size small to medium.
 
The shirt is about 19 inches from the ruffle to the hem and the skirt is 25 inches from the waist to the hem.
 
All Mexican dresses are almost one size fits all. So this could fit a petite woman or tall young girl.