Several techniques are used in practice using the application of an electric field in order to mitigate corrosion of reinforcing steel and protect structures from deterioration. These techniques include among others electrochemical chloride extraction electrochemical realkalization cathodic protection and removal of contaminating ions from concrete. Even though these techniques have been well-established and applied in practice less attention is given to the mechanisms of ion movement inside the pores of the cement paste under the application of an electric field. This paper describes the mechanisms of ion movement inside the pores of concrete at the microscopic scale with reference to the electrical double layer and the zeta-potential of the pore walls. The similarities and differences among the different electrical techniques applied to reinforced concrete are presented. The paper also discusses the parameters that control the effectiveness of these techniques.