I ordered a medium, normally I wear a small, but I read the reviews and ordered a size up. I should have ordered a small because the medium is a lot bigger (around) than I wanted and isn't very form fitting. The shirt is really low cut, but I wear an undershirt with it and it looks great. The material is soft and thin, but I like how thin it is; very comfortable and light. On me, the shirt is a little short. I have pretty long arms and I was worried about the sleeves not fitting properly, but they fit perfect. I've gotten several compliments on how cute the shirt is.