I almost never buy shirts online, because every time I have, the fit has never been right.  This is an exception.  I read the reviews, and felt I had a grasp of how this fit.  And it fits perfectly!  For reference, I am 5'5 and 125lbs, and I went with the small as another reviewer around my weight had recommended.  It's not too big, and not snug either, which is exactly how I like my work shirts.  It is a very thin material, but is incredibly comfortable to wear.  Also, while I think this in white would be somewhat sheer, in black its fine and can be worn without a cami underneath.  The length is perfect too, as I wear polo's untucked and the item picture on the model accurately portrays where the length sits.  It's hard to find women's polos in stores, especially ones that have the right fit, as the stores you can find them in typically carry the large variety of...1 brand only.  For the price, this is exceptional!  I will be purchasing more of these.