The presentation outlines the continuing demand for minerals and its impact on mineral resources. The trend is towards larger and deeper mineral deposits.

The focus is on the effects of depth on mining activities and in particular rock pressure. The period from 1950 onwards has seen an unprecedented increase of knowledge in rock mechanics and the development of the rock engineering discipline. This has resulted in a paradigm change from rock support to rock engineering design. The implications of this shift are most noticeable in deep mining.   Once the rock stresses exceed a value of about 0,4 of the compressive strength rock failure of excavation walls is unavoidable. In the case of strong rocks this situation is reached at depths   in excess 1500 m and Scandinavia with the exceptionally high primary horizontal rock stresses already at a depth of about 1200 m.  The emphasis of the rock engineering design is on taking advantage of the inevitable stress changes resulting from rock excavation. Some rock volumes become more highly stressed than before excavations and others become stress relieved. The digital revolution has made it possible to calculate these changes even for the most complicated mining situations. This has made it possible in some instances to extract mineral deposits well in excess of 3000 m depth. The thrust of deep mine design is now on stress management, i.e. to create favorable environments for mineral extraction. In South Africa massive gold deposits are extracted at depth in excess of 3000 m in the stress shadow of special destressing excavations. Similar concepts are now being evaluated for steeply dipping relatively massive ore deposits. The objective of these concepts is to extract the bulk of the deposit in destressed ground and place the vital mine infrastructure in destressed ground as well. This opens new avenues for the extraction of deep mineral deposits. Deep mining requires foremost active rock stress management and support should be seen as the last resort. 

As with most developments of revolutionary nature the implementation requires other changes as well such as the development of novel mining systems and equipment and changes in the organizational structure of deep mines.  In the case of rock engineering it requires the understanding of senior management for the need to establish a competent, well trained and equipped rock engineering infrastructure which becomes actively involved all matters requiring rock engineering expertise such as mine planning, production scheduling excavation support and risk management. In some major mining countries the need for competent rock engineering personnel a strong engineering function has been recognized and is prescribed by law.