Abstract: A shielding system for an enclosure wherein strips of shielding material including a layer of metal, for example, metal foil or gauge metal, are placed on the walls of the enclosure in an overlapping or abutting relationship, with shielding tape between the overlapped portions or overlying the butted seam. The shielding tape preferably consists of an electrically conductive nonwoven mat of entangled fibers which is laminated on one side to metal foil and which is bonded on the other side to the metal substrates using nonconductive adhesive. The entangled fibers penetrate the nonconductive adhesive and contact the surface of the metal substrate to provide an electrical continuity that seals the seam against leakage of electromagnetic radiation.