My daughter needed a white, short-sleeved leotard to perform with our professional ballet company's The Nutcracker. This leotard was perfect! She loved how soft and comfortable it is. And she also loved that it is not cotton. It fit my very thin, narrow 11-year-old well. She is wearing a child size L in all leotards. We purchased a child L and it fit very well.
Ordered this in a medium 8/10, and it runs very small. My daughter couldn't even get it over her shoulders. Size up if any question or on the border of the next size. All the other girls on her team were the same way.