Ten years of cratering research at Sandia Laboratory are reviewed and related, along with the work of others, to the development of explosive excavation technology. Single-charge experiments gave empirical relationships between crater dimensions and energy release, burial depth and medium. Energy release spanned the greatest range in desert alluvium, from 250 to 1 000 000 lb of explosive. Dimension depth-of-burst curves have been established for two kinds of alluvium, for dry-lake playa, for tuff, and for basalt rock. Dimension depth-of-burst curves and relations between crater dimensions and energy release also were established for continuous line charges in drylake Playa. Experiments with row charges provided basic information for optimizing row-charge detonations in level terrain. Investigations then were extended to terrain with a single elevation change and later to terrain with more typical variations. Special canal-related problems included how best to excavate through high mountain regions with small charges detonated one at a time for use when safety considerations did not permit the more efficient detonation of larger charges in rows. Excavation in two vertical stages was also examined, with the finding that, to be effective, a crater from the first stage must be wide enough not to unduly restrict ejection of material from the second. Using parallel rows of explosives, it was found it is more effective to detonate parallel rows one at a time rather than to detonate two or three parallel rows simultaneously. The possible use of explosives for removing overburden for ore bodies was examined using, in addition to parallel rows, four and five charge square arrays. Using optimum combinations of spacing and burial depth, these arrays removed three times more overburden than a single charge of comparable energy at the same depth.