Developments in Yarn Spinning Technologies covers the many advances that have occurred over the last 15 years. Besides improving production, these developments are driven by sustainability and energy efficiency. Although an area such as ring spinning has been proven as the most popular technology in this area, there have been various developments that have superseded in recent times. Similarly, rotor spinning, as the second most popular spinning system, has gone through many changes. Newer technologies in worsted, woolen, and other natural fiber spinning systems are also covered, along with the challenges posed through methods such as the circularity theory.