I'm 5'8" and 130 pounds with a larger butt and smaller 32 B/C boobs, I ordered a size M and had some size issues with this suit. It's great quality and really cute so I'm going to get it altered a bit. Essentially what happened is because I have larger thighs and butt I ordered a medium which fit perfectly on the bottoms, but my smaller boobs meant that the bottom band on the top which is not adjustable was loose. I would need it to be taken in almost 2 inches. Still a good product, but I would recommend if you are purchasing a medium to make sure your bra band size is larger than a 32 and ideally larger than a C cup (or some combination).