Abstract: A backplane power distribution system characterized by generally uniform current densities so as to be capable of handling very high levels of current. This is achieved with a stepped backplane construction. For example, in a system having, in order, a first conductive layer, a first dielectric layer, a second conductive layer, and a second dielectric layer, the second conductive and dielectric layers extend transversely beyond the first conductive and dielectric layers to present a substantial exposed area of the second conductive layer. Typically, a rectangular metal bus bar is bolted to the backplane to make contact with the exposed area, and power supply connections to the bus bar are made in any convenient manner. The backplane is preferably first laminated with all layers coextensive, and portions of the first conductive and dielectric layers then removed by milling.