This paper reviews the significant technical contributions to nuclear excavation of the past few years including (a) the effect of improved explosive design on radioactivity in fallout patterns, (b) the prediction of radionuclide concentrations airborne to extended times, (c) new information on seismic damage, and (d) cratering mechanics. The major past cratering experiments are discussed in terms of how their theoretical analyses have contributed to the present predictive capability of cratering mechanisms and dimensions. Seven concepts for the application of nuclear excavation are presented, and the nuclear effects associated with them are assessed.