Abstract: The present invention is concerned with multilayer printed circuit boards which have more than a single plane of interconnection conductors spaced away from a common plane, such as an earth or power plane. In such a case the conductors of the interconnection layers form transmission lines having respectively different impedances, depending on their distances from the common plane. The invention contemplates a pattern of conductive areas distributed over one of the surfaces of the multilayer board, the surface chosen lying on the opposite side of the planes of conductors from the common plane, the pattern configuration being chosen more nearly to equalize the impedances of the conductors. The areas of the pattern are preferably connected to the common plane.