the present invention provides a method of electrochemical polishing of a workpiece using a polishing pad having a cellular polymeric layer overlying a conductive substrate , the cellular polymeric layer having a thickness less than 1 . 5 mm ; wherein the cellular polymeric layer comprises a plurality of pores that extend through the thickness of the cellular polymeric layer from a polishing surface of the cellular polymeric layer to the conductive substrate ; and wherein the plurality of pores exhibit a diameter that is smaller at the polishing surface than at the conductive substrate .