This dress runs small. I weigh 111 lb and the small fit very weird! It zipped up across the back and it was skin tight, there is no stretch at all in this fabric! I always wear a small one I felt suffocated by this dress. I actually felt like I was going to split it! Because there's no give and the fabric is thin! I can't wear this in public I'm afraid it'll break and I'll be naked! Which leads me to the problem with the back... The straps are normal in the front but when it gets to the back they have extra fabric in them and they just sort of hang loose in the middle of your back. You can sort of see this in the model pictures, but it looks like she's probably clipped or taped to hold it more in place. It's just a weird all around fit. It's also shorter than it shows in the picture.