The concept of the 'worm gear' dates back to ancient times. Over the centuries, the design and use of this gear has evolved and improved. It describes a gear that contains a spiral or 'worm' like groove in it. Its early applications mainly involved the drawing of water, but today it has many varied applications - from power transmission to manufacturing. This comprehensive professional reference on the subject covers not only the design and manufacture of worm gears, but also issues regarding performance, maintenance, failure analysis, as well as applications. The author has extensive experience in the field and has written this book for gear designers, users and manufacturers, gear users, as well as for mechanical engineering students.