A three-dimensional (3-D), time-dependent, magnetohydrodynamic (MHD) model is used to simulate the interplanetary propagation of a disturbance that started in the low corona via the destabilization of a southern hemisphere helmet-streamer on April 14, 1994. A severe geomagnetic storm occurred at Earth, and a forward-reverse shock structure was detected at Ulysses (3.2 AU) at E30 ¿S60¿. The model is initiated at 18Rs (where Rs is the solar radius, 6.95¿105 km) within the supersonic and super-Alfvenic region of the solar wind; hence no consideration is given to the disturbance's evolution from ~1Rs to 18Rs. We refer to the interplanetary disturbance as an interplanetary/coronal mass ejection (ICME) to indicate that it may be relevant to what has been referred to in the literature as a CME but is not related to the flux rope or magnetic cloud that has also received much attention. We find that the 3-D MHD model, with a simple pressure pulse (suggested by Yohkoh soft Xray observations), provides a satisfactory comparison with the SSC timing at Earth and the Ulysses observations.¿ 1997 American Geophysical Union