Conservation and preservation of our cultural heritage requires an understanding of the complex chemical, physical, and biological threats to its integrity. Recently, MCI’s Director Robert J. Koestler chaired a panel “Microorganisms in subterranean environments” for the French Ministry of Culture at their International Symposium Lascaux and Preservation Issues in Subterranean Environments, February 26-27, 2009. This meeting was convened to investigate anthropogenic-induced changes over the past decade to one of the greatest cultural treasures of the western world – the Paleolithic painted cave at Lascaux, France. The almost 2,000 vivid and vivacious animal paintings made from luminous iron and manganese oxide, approximately 16,000 years old, are suddenly threatened by the rapid growth of garden-variety soil molds. Some experts proposed that the mold damage was a consequence of global change, although this is still unproven (see Science News, June 6, 2009, p. 12.) On April 20-22, 2009, MCI convened its own international workshop on the topic, Biocolonization of Stone: Control and Preventive Measures, to provide a discussion forum for biologists, material scientists, and conservators with expertise in microbial (bacterial and fungal) damage to stone. The workshop explored new methods to detect and prevent microbial deterioration and colonization, and future directions for collaborative research. The conference papers will be published as a volume in Smithsonian Contributions to Museum Conservation. MCI’s chemical analysis, including fine-scale physical mapping of surface details, developed in our Mongolian Deer Stone project, have shaped our current understanding of Lascaux’s paintings and now this knowledge will help us to mitigate the current environmental and microbiological threats to Lascaux. By combining chemical, physical, and biological approaches and concepts, MCI is better able to preserve cultural heritage for future generations.