Industrial Process Tomography (IPT) methods are reviewed in brief in terms of their underlying technology, goals and their typical limitations when applied to multi-component processes, where the material distribution depends upon a range of physical or chemical states. Multi-dimensional enhancements and data fusion methods are discussed: in spatial terms where there is inhomogeneity in the distribution; in temporal terms of dynamic characteristics; and in specific component identification. This latter further dimension is discussed in terms of ‘excitation energy’, including multi-modal and multi-spectral ‘spectro-tomography’ systems. The paper concludes with a review of the potential of such methods.