Details are presented of the research and development of a computer program for the calculation of Rotor System Dynamic Response including foundation and pedestal flexibility effects. Eight-coefficient bearings are used to permit elliptical orbit rotor motions. The bearings are mounted in massive, damped flexible pedestals, which are themselves mounted upon a foundation structure with distributed mass and stiffness properties. The foundation is in turn, supported on a number of flexible-damped supports. Different foundation properties in the horizontal and vertical directions are included. The results obtained are compared with data by other investigations. Applications of the code are described which validate various aspects of the analysis and the computer program