I wore these under a dress to a gala. I am 5'9" and 140, and the medium fit good. I think I would have been a small under the sizing, but because this is designed to slim and hold you in, I wanted to error on the larger side instead of smaller so I wouldn't be uncomfortable. This also has a plastic band to help hold it up, which I didn't have a problem with it falling down. However, there is a large hole in the crotch of these, presumably so you don't have to completely undress to use the reSee full review