I've been looking for a flattering and unique top, and this is definitely it. I bought it in a medium and assumed it would be a bit oversized, but the fit is perfect. I wear a 28E bra (the mainstream equivalent size being 32C or 34B), and my ribcage is 27 inches around. There is still a little room to breathe, my chest isn't flattened (I find this creates a flattering amount of cleavage), and the adjustable straps allow for decent support. I can't imagine anyone would fit the small, unless you wear a 32B or smaller. The only caveat is the bikini, when stored, is a bit heavy and bulky, so if you're looking for something that is super lightweight and takes the least amount of space in your travel bag, this is not it (it doesn't feel heavy or bulky when wearing it, however). I think this bikini does double duty as a bathing suit and bustier - it looks great with high waisted pants or skirts!