Pixel-based tomography has been used with great success for medical applications where it is most appropriate but this approach does not always transfer easily to industrial applications. For example pixel-based image reconstruction from electrical impedance tomography measurements is well known to be an ill-posed problem and with high noise levels such tomograms cannot be reliable. An alternative approach is to use a parametric representation of the tomogram for which reconstruction can be better posed. The primary reason for parametric modelling, however, is interpretation. This paper compares parametric modelling to other methods and then gives an example of the method for an application to a hydrocyclone. Two tomographic modalities are discussed and the results from parametric modelling are validated. This example demonstrates the great power achievable from a parametric modelling approach to tomographic imaging of industrial processes. (C)2000 Elsevier Science S.A. All rights reserved.