I am normally a size 6 or even a 4 in some brands - with a 25'' waist and measuring only 5'2'' in height, so I bought the Vegas sequin dress in size 6 initially. When it came through, it felt too tight so I got a size 8 instead which fits perfectly. The dress is well made with great attention to detail and looks much more beautiful in reality than it does online - which is rarely the case with online shopping I find! Anyway, my only suggestion is to make sure you order one or two sizes bigger depending on your body shape as their clothes tend to run small. I have other Hybrid dresses (all size 6) and they are a perfect fit, very form hugging and with very good stitching so will get lots of use out of them for nights out. I think a good, sizing chart to make purchases easier for people is needed on the Hybrid website at the moment.