"We ordered the 8/10. My daughter is very petite and usually wears an 8. We were disappointed when the costume arrived. The hat was way too small. My daughter couldn't even get it on her head. The costume was snug around the back and too short! so, we returned it and got the larger size. It fits well. It's a little big around the neck and falls off her shoulder slightly. But, it works. The material is a little too thin. The belt does not stay in place. The buckle on the hat has to be pinned down to stay in place."