In the past few years, numerical studies of corona-interplanetary dynamics have been undertaken by many investigators. The results, as summarized by Wu et al. (1977), indicate that this approach seems very promising and worthy of further pursuit. So far, the calculations have been performed on two-dimensional codes, to simulate magneto-hydrodynamic flow in a meridional plane or in the equatorial plane. In order to fully account for the global features of the corona-interplanetary phenomenon, it is necessary to do three-dimensional calculations. Here we discuss some groundwork for the formulation of a time-dependent three-dimensional code.