In many fields of process industry, it is essential to be able to accurately measure the volumetric flow rates and mass flows of different materials flowing in the process pipes. To estimate the volumetric flow rate of a certain phase, the volumetric fraction and the flow velocity field of the phase in a cross-section of the process pipe need to be known. For velocity field metering, electromagnetic flow tomography (EMFT) techniques have recently been developed in our research group. This lecture gives an overview on the basics of the EMFT technique. Common measurement procedures and image reconstruction methods are reviewed and some latest results of the technology to measure single and two-phase flows are shown.