Modern rotating machinery, particularly turbomachinery, is frequently being designed to operate at higher speeds than in the past. Consequently, there is an increased need to balance high-speed rotors. The purpose of this book is to provide the engineering student or practicing engineer with a single, complete reference on high-speed rotor balancing. To this end, a detailed analytical background and practical application procedures are presented for each of the principal high-speed rotor balancing methods, i.e. modal balancing, influence coefficient balancing and the Unified Balancing Approach. This information is supplemented and supported through a presentation of the theoretical development of synchronous rotor vibration and a brief overview of rigid rotor balancing techniques and machines. This is the first time this material is available in a single, concise volume, together with detailed descriptions of application procedures.