solution of structural dynamics problems is introduced in this new edition. This program was selected from among the various professional programs available because of its capability in solving complex problems in structures as well as its wide use in professional practice by structural engineers. SAP2000 includes routines for the analysis and design of structures with linear or nonlinear behavior subjected to static or dynamics loads; (material non-linearity or large displacements non-linearities) and may be used most efficiently in the microcomputer. The larger versions of SAP2000 have the capability for the analysis of structures modeled with virtually any large number of nodes. This new fifth edition of the book uses, almost exclusively, the introductory version of SAP2000 which has a capability limited to 25 nodes or 25 elements. A CD ROM containing the introductory version of SAP2000 as well as the educational set of th the program developed by the author is included in this 5 edition of Structural Dynamics: Theory and Computation. The set of educational programs in Structural Dynamics includes programs to determine the response in the time domain or in the frequency domain using the FFT (Fast Fourier Transform) of structures modeled as a single oscillator. Also included is a program to determine the response of an inelastic system with elastoplastic behavior, and another program for the development of seismic response spectral charts.