High-energy particle accelerators are as diverse as their uses, which range from scientific research in fields such as high-energy physics, materials science and the life sciences, to applications in industry and medicine. Despite the diversity of accelerators, the particle beams that they are designed to produce behave in ways that share many common features. Beam Dynamics in High Energy Particle Accelerators aims to provide an introduction to phenomena regularly encountered when working with beams in accelerators; from the basic principles of motion of relativistic particles in electromagnetic fields, to instabilities that can affect beam quality in machines operating at high current. This book assumes no prior experience with accelerator physics and develops the subject in a way that provides a solid foundation for more advanced study of specific topics. As well as including numerous revisions and improvements in the text, this second edition features substantial new material, including sections on fringe fields in multipole magnets, Verlet integration for particle tracking, and measurement of beam emittances. References and discussions of current topics have been updated. As with the first edition, the aim is to provide practical and powerful tools and techniques for the study of beam dynamics, while emphasizing the elegance of the subject and helping the reader develop a deep understanding of the relevant physics.