Hadjigeorgiou, J 2012, 'Where do the data come from?', in Y Potvin (ed.), Deep Mining 2012: Proceedings of the Sixth International Seminar on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 259-277, https://doi.org/10.36487/ACG_rep/1201_19_hadjigeorgiou (https://papers.acg.uwa.edu.au/p/1201_19_hadjigeorgiou/) Abstract: Deep and high stress mining poses a significant number of geotechnical challenges. Despite considerable improvements in almost every technological aspect of the design and operation of mines at depth and under high stress, the weakest link remains the quality and quantity of data. This paper addresses certain inconvenient facts on how data are collected and managed. The case is made for a disciplined approach to data collection, analysis and interpretation. Unless this is implemented in a systematic way, it will not be possible to capitalise in gains made from improved engineering tools. A further concern is that for mines operating at depth, the margin of error due to inadequate or inappropriate data is much smaller, and the repercussions more severe, compared to shallow mines.