The influence of attachments and substructure on the vibration of a plate is a very important problem in noise and vibration control. This paper presents several examples of using an energy viewpoint with experimental data. The normal velocity of each plate, measured with a laser vibrometer or in some cases obtained from analytic calculation, is then used to calculate the structural intensity and force distribution. The structural intensity and force distribution are then used to locate single and double forces applied to a plate with some limitations. In addition, a rib attached to a plate and a constrained layer damping patch attached to a plate is studied. The energy absorbed by the rib and the force exerted by the rib in response to the waves incident on the rib are discussed. Results also show that a constrained layer damping patch is more effective in absorbing shear and bending vibrational energy than in absorbing twisting energy and that the damping patch does not apply a normal reaction force to the plate.