I sell Tory Burch on eBay and get a lot of questions about sizing.  Below is the size chart taken directly from ToryBurch.com, hope this helps when shopping on eBay!

Womens Size Chart

                            XS                        S                        M                         L                   XL

Chest/Bust         34-35                  36-37                 38-39                   40-41             42-43

Natural Waist     26-27                 28-29                  30-31                   32-33             34-35

Low Waist       31 1/4-33 1/4     34 1/4-35 1/2    36 1/4-37 1/4   38 1/4-39 1/4    40 1/4-41 1/4

Hip                 34 1/4-35 1/4      36 1/4-37 1/4    38 1/4-39 1/4   40 1/4-41 1/4    42 1/4-43 1/4

                          0            2              4          6           8          10           12         14

Chest/Bust      33 1/2     34 3/4        36       37         38          39        40 1/2    42 1/4

Natural Waist    25        26 1/4     27 1/2   28 1/2   29 1/2   30 1/2      32       33 3/4

Low Waist      31 3/4        33        34 1/4  35 1/4   36 1/4   37 1/4    38 3/4    40 1/2

Hip                   34        35 1/4     36 1/2   37 1/2   38 1/2   39 1/2      41        42 3/4

Measuring Instructions:

Chest/Bust- Measure under the arms, around the fullest part of the chest, keeping the tape measure parallel to the ground.

Natural Waist- Measure around the waist at the navel, keeping the measuring tape parallel to the ground and one figer between the tape and your body.

Low Waist- Meawure 2" or 3" below the natural waist, keeping the meausring tape parallel to the ground and one finger between the tape and the body.

Hip- With your heels together, measure around the fullest part of the hips, keeping the measuring tape parallel to the ground.