Usually I am hesitant to order a size up even when the reviews say the item runs small, but definitely SIZE UP! I am typically a small/medium in fashion nova, I ordered the medium first and while it zippered I couldn't get it to pull over my chest. There is ZERO stretch! I ordered the large and it fits perfect. Great quality corset and it looks amazing on. I'm happy I was able to exchange it for a size that fits, because I love this top.