This volume describes the rotordynamic considerations that are important to the successful design or trouble-shooting of a turbomachine. It explains how bearing design, fluid seals and rotor geometry affect rotordynamic behaviour (vibration, shaft whirling, bearing loads and critical speeds), and describes two successful computational methods for rotordynamic analysis in terms that can be understood by practicing engineers. Descriptive accounts are given in several areas of the field and important mathematical or computational concepts, describing equations and formulae in physical terms for better understanding, are presented. Tips for trouble-shooting unstable machines are offered, together with practical interpretations of vibration measurements.