The invention provides a method for polishing one or more layers of a multi-layer substrate that includes a first metal layer and a second layer comprising (i) contacting the first metal layer with a polishing system comprising a liquid carrier, at least one oxidizing agent, at least one polishing additive that increases the rate at which the system polishes at least one layer of the substrate, wherein the polishing additive is selected from the group consisting of pyrophosphates, condensed phosphates, phosphonic acids and salts thereof, amines, amino alcohols, amides, imines, imino acids, nitriles, nitros, thiols thioesters, thioethers, carbothiolic acids, carbothionic acids, thiocarboxylic acids, thiosalicylic acids, and mixtures thereof, and a polishing pad and/or an abrasive, and (ii) polishing the first metal layer with the system until at least a portion of the first metal layer is removed from the substrate.