It's honestly so perfect. I'm 5'4", 158 lbs and I bought a size medium. The built in bra is a good fit, I'm a cup size 36D and it's got enough fabric to probably go up past a DD. I like the length, and it's tight enough it doesn't ride up quickly (does ride a little, but not alot). I've been able to dress it up and down a number of times now. I usually wear a thong with it and you can never see the underwear lines - its made out of a thicker material. It's perfect! It's the perfect little black dress!