The interaction of living materials with inanimate materials via physical and chemical reactions poses an acute danger for the longevity of our cultural heritage, as long as it exists in the material form and not in that of the invincible word. Thus our concern for cultural heritage must reach the same level as our current concern for the conservation of the natural environment, both through public education and through the development of guidelines for scientists, restorers, and conservators. To this end, this volume explores the status of scientific and humanistic approaches to our cultural heritage and the disequilibria in research and related disciplines. Particular areas discussed include the processes of aging and decay, the durability of material objects, the acceleration of the patina and decay processes in cultural materials through environmental and biological hazards, and the techniques that are both available now and under development for protecting, conserving, and restoring our cultural heritage. This volume is a multidisciplinary attempt to set up dialogue between those who do research and those who practice conservation and restoration. It will be of interest to anyone interested in cultural heritage and, in particular, to those art historians, archeologists, architects, communication scientists, chemists, biologists, mineralogists, and physicists who are also seeking to bridge this gap. Goal of this Dahlem Workshop: to evaluate processes that contribute to change in objects, cultural materials, and artifacts, and to find appropriate ways of conserving them.