Selected milestones in the development and use of electrical tomography in powder conveying,slurry processing and multi-phase flow are highlighted.The ability to map concentration in opaque mixtures under process-realistic conditions was a major innovation for the method and has had far reaching implications.Subsequent developments have enabled velocity information to be abstracted resulting in the ability to measure component flux and motion. Selected milestones in the development and use of electrical tomography in powder conveying, slurry processing and multi-phase flow are highlighted. Ability to map concentration in opaque mixtures under process-realistic conditions was a major innovation for the method and has had far reaching implications implications . Subsequent developments have enabled velocity information to be abstracted resulting in the ability to measure component flux and motion.