Dynamic three-dimensional image electrical capacitance tomography sensor system is disclosed. The technique generates, from the measured capacitance, a whole volume image of the region enclosed by the a geometrically three-dimensional capacitance sensor. A real time, three-dimensional imaging of a moving object or a real time volume imaging (i.e., four-dimensional (4D)) allows for a total interrogation scheme of the whole volume within the domain of an arbitrary shape of geometry to be implemented. The system comprises a 3D capacitance sensor, data acquisition electronics and the image reconstruction algorithm which enables the volume-image reconstruction. The electrode shape of the capacitance sensor can be rectangular, triangular, trapezium, or any shape to enclose a 3D section of the measuring domain and to distribute the electrical field intensity in three directions with equal sensitivity strength. The image reconstruction algorithm reconstructs simultaneously the image voxels in a three-dimensional array. The tomography sensor system may be multimodal.