A fast procedure is given for decomposing networks in minimally interconnected subnetworks. A minimal subnetwork is a group of components and electrical nodes for which there is no other subgroup having less terminals than the subnetwork. The procedure uses a property of 0-minimal subnetworks, which reduces considerably the computation time for obtaining the minimally interconnected subnetworks; a 0-minimal subnetwork is one in which there exists at least one subgroup with the same number of terminals as the subnetwork, and there is no such subgroup with less terminals than the subnetwork. The procedure is compared with a previously published technique.