The mandate of the National Park Service is to preserve and protect the nation's natural and cultural resources which are entrusted to its care. These guidelines address the needs of the historical collections within the exhibit environment and attempt to minimize loss and deterioration. A systematic program for collections care has been developed by the Park Service curators and conservators to safeguard these non-renewable resources. The challenge has been to create an inviting and stimulating exhibition environment that does not endanger the collections on display. To reduce the risk of damage and unnecessary deterioration to these objects, particular care must be taken to ensure that exhibition design and construction utilize the highest standards and incorporate the most current conservation information. Through cooperation and collaboration, we can eliminate all unnecessary damage occurring within our exhibits. To accomplish this, however, we must concern ourselves with the total exhibit environment which is created through the interplay of the environmental conditions present, the exhibit's design and the materials used in its fabrication. The following guidelines are intended to provide conservation parameters for the safe and protective exhibition of museum objects. These conservation guidelines are in accord with the Director's Special Directive 80-1 (Revised 1990) regarding preservation and protection standards for museum collections.