Boning is a technique used in dressmaking to give a garment stiffness and structure. It is a long, flat, and stiff material that is inserted inside the clothing. Boning is used to stiffen an area in a garment where you want vertical support, such as in a strapless dress, to keep the dress from falling down. It is also used to stand up a collar, keep folds or pleats in place, and add structure to collars, pleats, and necklines. There are different types of boning, including white steel boning, spiral steel boning, hoop boning, plastic boning, fusion coated boning, rigilene boning, lacing bones, extra-wide bones, natural corset boning, whalebone (baleen), and featherbone. If a pattern calls for boning, it will indicate which seams require boning. If not, you can decide where you want to add the boning. At minimum, you’ll want to add a piece of boning to each side seam. Depending on the design, you may want to add boning to the vertical seams as well, along the vertical darts at the back or along center front or back. The more boning you add, the more structured your bodice will be.