Abstract: A method and system for monitoring an electrotherapy treatment applied to a subject in need of such therapy. An ultrasound transducer array is positioned adjacent a tissue of the subject to which the electrotherapy treatment is to be applied. The electrotherapy treatment is administered to the tissue as a plurality of ultra-short electric pulses which generate an electric field in the vicinity of the tissue. The ultrasound transducer array detects acoustic signals which are induced by the electric field. The detected acoustic signals are then used to construct tomographic images which represent the electric field generated by the electrotherapy treatment during real-time.