This was very cute, but needs more confidence than I have.  5'9 and size 4/6, ordered a Medium and it fit great.  The top was fantastic, but the bottoms just don't have enough coverage in the back.  I even checked to make sure I didn't have them on backwards...ha!  I wish they had an option for a fuller bottom, because everything else was perfect and I just can't quite pull off the cheeky bottoms.