I am 5'6" and 140b, i'm usually a s and that is the size i bought. i loved the fit of the top and wore it immediately. then i washed it just as the instructions said and the liner shrunk about 3" (just as another reviewer stated) and the sleeves were much tighter and a little shorter. however, i loved the top so much that i took the top back to the store and exchanged. the store was super understanding about it and i was able to order the same size. it's back ordered, but once i get the new top