This introductory text for electrical engineering students is concerned with the principles of electromechanical energy conversion, its utilization within particular drive systems, its practical implementation via power electronic circuitry and its relevance to intergrated power networks. The early chapters of the book incorporate essential aspects of electrical conductive, electrostatic and magnetic fields as conventionally understood. Further chapters are devoted to an understanding of rotating machine armature windings, brushless dc machines, stepping motors and switched reluctance drives. The essential characteristics of representative converter and inverter circuits are included in the text, with descriptions of behaviour emphasizing the features relating to energy transfers.