I purchased this dress in a Small. Pre-pregnancy, I usually wear a size 4 dress which equates to either an XS or S in regular clothes. I tried it on and it practically swallowed me whole. I found this dress on another site and discovered that the S is intended for sizes 8-10! Wow. So, for those purchasing this dress, XXS = sizes 2-4, XS = 6-8 and so forth. Please keep that in mind when ordering.