The use of an electric field modifier to boost the current output of a discrete sacrificial anode to enhance its protective effect and to direct the current output in a preferred direction to improve current distribution in the galvanic protection of steel in hardened reinforced concrete elements exposed to the air is disclosed. In one method a combination comprising a sacrificial anode (21) and an electric field modifier (25) and an ionically conductive filler (28) is embedded in a cavity formed in a concrete element and the sacrificial anode is directly connected to the steel (22). The modifier comprises an element with a side that is an anode (27) supporting an oxidation reaction in electronic contact with a side that is a cathode (26) supporting a reduction reaction. The cathode of the modifier faces the sacrificial anode and is separated from it by the filler (28). The filler contains an electrolyte that connects the sacrificial anode to the cathode of the modifier. The anode of the modifier faces away from the sacrificial anode. The reduction reaction on the cathode of the modifier may substantially comprise the reduction of oxygen from the air.
