A theoretical and practical understanding of unbalance and misalignment in rotating equipment is presented here. These two conditions account for the vast majority of problems with rotating equipment encountered in the "real world." Numerous examples and solutions are included to assist in understanding the various concepts. Included is information on vibration and how it is used to determine the operational integrity of rotating machinery. Also detailed are the relationships between various vibration characteristics which provide an understanding of the forces generated within operating machinery when conditions of unbalance and misalignment are present. Resonance and beat frequencies are detailed along with sources and cures. Also covered are proper inspection procedures, single plane and dual plane methods of balancing rotating equipment, the three circle method of balancing slow speed fans, advanced rim and face method of precision alignment, and the reverse indicator method of alignment plus much more to fortify the learning experience.