Thank goodness for a nice white basic tee that is not see through! i go back and forth between an xs and s depending on how i want an item to fit - i don't like things to be too form fitting because i still have a little post-baby pooch. i went with a s in this shirt and it works well. my only complaint is that the neckline is not totally straight - where the seam comes up from under the arm to hit the neckline it bumps out a little bit. but it's a great nicer basic that will go well with almost