This paper deals with the use of three electromagnetic non-destructive in situ techniques to assess concrete conditions: electrical resistivity, capacimetry, and ground-penetrating radar. It shows the potential of these methods to monitor the ingress of water and chlorides into concrete. The electro- magnetic properties that are studied here are dielectric permittivity and electrical resistivity, both sensitive to volumetric water content and chloride content. Results are presented from an experi- mental study conducted on concrete slabs (and corresponding core cylinders) in a controlled labora- tory environment. Then, the discussion is focused on the ability of three electromagnetic techniques to assess the depth of the ingress front of different salt solutions and to discern between the 3 NaCl concentrations (0, 15 and 30 g/L).