Our knit style is one size tie up but comes in 3 different lengths, please measure to your height depending on your style, details below.  Skirts lengths have been designed to allow for heels, please size down if you will wear flats: Petite 35" length: Order if you are a shorter girlie or if you want to wear the skirt low waisted or with flat shoes Regular 40" length: Order if you are regular hight or if you want to wear this with heels low waited  Tall 43" length: This is for the taller girls (with heels)  Please read the care instructions for all Beyond Swim Products.  Model is wearing our regular length for reference