The electronic equipment in a guided missile during flight is subjected to vibrations carried from the propulsion unit through the frame to the deck on which the equipment is mounted. It is desirable to keep the amplitude of these vibrations in the sensitive electronic units as low as possible. To accomplish this, vibration absorbers may be incorporated between the frame of the missile and the equipment deck, or the deck itself may be constructed so that it acts as a continuous vibration absorber. Such a deck may be made in the form of a sandwich plate, that is, a composite plate-like structure having two thin metal faces separated by a thicker core of some material which has dissipative properties. In this report two types of sandwich plates having visco-elastic cores and one type of dry friction sandwich are studied. Some comparisons are made on the damping effectiveness of each kind of sandwich plate studied.