Alternative methods of preventing the corrosion of mild steel reinforcement in reinforced concrete structures are reviewed. Stainless steel may be used as an alternative, but this is expensive and may still corrode if welded or in contact with mild steel. Galvanised mild steel is cheaper, but the steel composition must be suitable for plating, suitable passivated agents must be identified, and service life is adversely affected by high chloride concentrations. Cathodic protection is effective, if the applied potential is matched to the chloride concentration. The initiation of corrosion may be retarded by adding inorganic ( calcium nitrite ) and organic ( amino alcohols ) inhibitors to the concrete at the time of mixing. 21 refs.