In these years of constant growth and further development for our company, research and development has become more and more important, and has allowed us to be at the forefront in our business sector, where innovation is the obvious and decisive factor. It has therefore been consistent with our everyday business philosophy to involve ourselves deeply in writing and printing this handbook, which is designed to recognize the capacity and hard work of all employees working successfully in the Bonfiglioli Group. The book is intended to be a concrete contribution by Bonfiglioli Riduttori S.p.A. to the development and application of power transmissions. The book is addressed to all who have technical dealings with power transmissions, from university students to engineers active in the workplace. For this reason we have invited the cooperation of four prestigious professionals - Darle W. Dudley, Jacques Sprengers, Dierk SchrOder, and Hajime Yamashina - in the knowledge that only through the cooperation of the leading specialists in the field of power transmissions could we develop a truly useful and helpful handbook. It has been hard work, but we are sure the reader's appreciation will amply reward our efforts.

For more than 30 years the book Practical Gear Design, later re-titled Handbook of Practical Gear Design, has been the leading engineering guide and reference on the subject. It is now available again in its most recent edition. The book is a detailed, practical guide and reference to gear technology. The design of all types of gears is covered, from those for small mechanisms to large industrial applications. The presentation is designed for easy reference for those involved in practical gear design, manufacture, applications and problem solving. The text is well illustrated with clear diagrams and photographs. The many tables provide needed reference data in convenient form.