Third installment of a series on leno weaving, covering design of figured three-end leno fabrics woven with slotted steel doups on dobby looms. It explains the open and crossed shed positions of the slotted doup and describes several sample fabrics (diamond, all-over, scroll and quadri-symmetrical patterns) with drawing-in drafts and chain drafts. The final pages give practical loom settings for leno, including harness and doup standard heights, leasing, slackener setting, selvages, and reeds.