I am 5'9", weight 180lbs, have 36DD/DDD chest, have an hourglass figure, and wear a size 12 or 14 (depending on the brand). I bought a L. It fits great, and looks good. It's a little lower cut than I'd like on the side without the strap, which is why I knocked a star off. It doesn't stay up that great and slides down on that side, so I really have to watch to make sure that my left breast doesn't pop out when I'm swimming. Looks good on my hourglass shape otherwise. Neon green is fun too, but bleeds--so don't wear it with light colors or it will bleed when wet (I've washed it and worn it 3 times too and it still bleeds).