The Main Himalayan Thrust fault system and its splays, particularly the sections underlying western Nepal, Bhutan, and adjacent India, is expected to produce great earthquakes, whose consequences could be greater than any recent or historic earthquakes, particularly given the region's rapid population growth. This session welcomes paleoseismic, geodetic, and other research bearing on the recurrence intervals and nature of large earthquakes along this margin. We invite analyses that characterize shaking and the natural, human, and economic consequences anticipated from such events. We encourage discussion of challenges in preparing for, responding to, and recovering from earthquakes strongly affecting two or more nations simultaneously. Our intent is to characterize the extent of our scientific knowledge, understand sources of uncertainty, and motivate preparation by relevant local, national, and international authorities and agencies by presenting the scientific consensus concerning the likelihood of human tragedy in the region.