A computer program WAVE has been developed in CSIR-MiningTek as part of its elastodynamic research in the Rock Mass Behaviour project. It allows efficient elastodynamic modelling of two- and three- dimensional orthogonal geometries on a personal computer. Today, models with over a million zones can be solved within acceptable run-times. This paper introduces the program WAVE, its features and the scope of problems it can examine. Some validation tests are described and example applications of the program are given.