The disposal of heat emitting nuclear fuel waste in a manner that will not pose a threat to human health and the environment continues to be a problem of concern to many countries that have used nuclear power for energy production. In certain instances, the spent fuel has accumulated for over four decades and is kept at the reactor sites. There is general consensus that disposal of such waste is best achieved through deep geological disposal and monitored storage. The construction of such underground disposal schemes requires a knowledge of how the natural geological rock and the engineered geological barriers will behave under the action of groundwater movements, thermal loads and other environmental effects for lifetime that are beyond the range of human experience in engineered activities. This lecture will discuss certain issues related to technologies that have been proposed for deep geological disposal of heat-emitting nuclear fuel waste.