In the description, it suggests sizing up because the dress runs small and sizing up again if you are bigger than a C cup. This would make me an 8 (I usually wear a 4). Unfortunately, it was too close to my event and I was only able to order a size 8. I was worried it would still be too tight on the bust, but instead it was big. With a bra underneath it stood up, but it was definitely a size too large. I would advise other D/DD cups to go up just one size and ignore the suggestion to go up an additional size because the dress runs true to size. I also knew going into it that the dress would be very long. I was wearing five inch heels and the dress was still dragging on the floor (I'm 5'2''). Watch out for the length. Despite the fit issues, I love this dress and would absolutely recommend it.