The collected reserves of the world's natural heritage have been slowly deteriorating over the past two centuries. The extent and understanding of the processes involved are as yet largely indocumented and unknown. Recent surveys at national level and by conservation specialists reveal that some areas are at crisis point through the unchecked growth of collections, poor training in conservation and collection management procedures, and pure indifference. Key areas of taxonomic, systematic and environmental research on material from collections, now and in the foreseeable future, depends upon analytical technology. The knowledge of the nature and effects of deterioration processes and the techniques used to check them must be achieved scientifically. The nature of some of the major conservation problem areas in biological and earth science collections will be outlined as an introduction the the General Session: Collections at Risk and the arguments for proactive, preventive and passive preservation strategies will be considered.