Fabric folded into a number of pleats that are pressed all in the same direction. They are chic, usually completely vertical but may be shaped to taper–these are much more complicated to make, but look especially good on the deep skirts of loose covers–for this you need a good budget or masses of time.
Knife-pleating is structured and tailored style, a very smart way to add a soft, feminine finish to the room. It is much less girly than frills, and more suitable for urban rooms. I have designed knife pleats for pelmets, chair skirts, curtain edges and deep hems, bed and sofa valances, and decorative cushion edges.