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The nearly instantaneous formation of large, deep sinkholes in developed areas in South Africa has cost the lives of 39 people and has destroyed buildings worth millions of dollars. Rapid urbanization around the major metropolitan centers of Johannesburg and Pretoria forced developers to consider land underlain at shallow depth by dolomitic rocks. Thus,;it became necessary to develop evaluation methods and investigative techniques to determine the risk of surface instability before development could commence. The South African Council for Geoscience is extensively researching the geotechnical properties of the weathering of dolomitic rocks, as well as establishing an interest group for applied studies on dolomite to further the education of interested parties and to standardize investigative and evaluation techniques. The formation of surface instability features in areas underlain by limestone and in arid regions of the country shows that the instability problem in South Africa is far more widespread than previously thought, but that the concerted efforts of the engineering geological community, led by the Council for Geoscience, will eventually lead to sensible and safe urban development.