If you have a larger butt, size up!
I wish I got this in a small because the small is longer (I got a small of the same dress in a different color, and I'm happier with the length). I can still wear this dress but it's on the shorter side for my liking. I absolutely cannot lift my hands above my head because the dress will be way too short. I do have a larger butt for my size, so maybe that is why. Otherwise, love this dress!