For sizing, i normally wear either xs or s in tops (i'm 5'7", 130lbs, 34a). i tried on both, and both fit, but the arm holes were a little too tight on the xs. i ended up picking the s because it felt most comfortable. when i tried on the ivory color, i could see my blue bra underneath, and it would require a cami. the black didn't. i love the embroidered design and ruffled neck. i agree the buttons on the back of the neck are a tad difficult to button, but it's not a deterrent.