At the Physics and Electronics Laboratory TNO much research is done in the field of computational electromagnetics (CEM). One of the tools in this field is the Finite Difference Time Domain method (FDTD), a method that has been implemented in a program in order to be able to compute electromagnetic scattering by complex objects. In this paper a parallel implementation of the FDTD code is presented. The implementation is used to investigate the efficiency of the code and to investigate the usefulness of such a parallel implementation, especially with respect to increase in problem size and speed up when compared to a conventional supercomputer. Results of some test computations were compared with results of computations performed on a Convex C230 supercomputer, which indicated a efficiency of 70% and a possible speed up of 4.7 times, with respect to the Convex C230. Current work is on the optimisation of the parallel implementation. © Springer-Verlag Berlin Heidelberg 1996.