This revised, updated textbook adds new focus on computational methods and the importance of vibration theory in computer-aided engineering to fundamental aspects of vibration of discrete and continuous systems covered in the previous two editions of Vibration of Discrete and Continuous Systems. Building on the book's emphasis on the theory of vibration of mechanical, structural, and aerospace systems, the author's modifications, including discussion of the sub-structuring and finite element formulations, complete the coverage of topics required for a contemporary, second course following Vibration Theory. The textbook is appropriate for both upper-level undergraduate and graduate courses.