Austin Hughes was a long-time member of the innovative motors and drives research team at the University of Leeds, UK, and has established a reputation for an informal style that opens up complex subjects to a wide readership, including students and managers as well as technicians and engineers.Bill Drury is an independent consultant in power electronics, electrical machines and drives (PEMD). He has 45 years industrial PEMD experience - Siemens, Rolls-Royce and for 20 years Technical Director of Control Techniques. He is a Chartered Engineer and a Fellow of the Institution of Engineering and Technology (IET). He is a Visiting Professor of Innovation at Bristol University and a Visiting Professor at Newcastle University.