For on-shore applications, the support structure for a rotating machine consists of a block foundation and base-frame (base plate) normally known as skid. Adequate dynamic analysis of support structures for rotating equipment is necessary to safeguard other machinery in the vicinity of the subject rotating machine, as well as ensure good conditions for the operation of the supported machine. The present method tries to achieve an under-tuned support structure which considers the machine mass and block foundation mass as one entity. The design procedure assumes that all vibrations are transferred to the machinery foundation irrespective of the type of machine. This paper endeavors to highlight that how and why current design procedures for support structures of rotating machinery should consider the stiffness ratio of the bearing support (casing) and the rotor-bearing system, With the advent of foundation damping methods, the size of foundation can be lowered with a correct deliberation on the subject.