The preservation and restoration of metallic objects that are or have been exposed to the environment is a highly interdisciplinary activity involving conservators, corrosion scientists, metallurgists, materials scientists, and others. The objects themselves may be new or old, large or small, industrial or artistic, but the physical processes involved are common to all, as is much of the related terminology in common use. To encourage cooperation among the specialists involved, a glossary of terms common to the several fields of study has been developed. The glossary was prepared by members of the National Association of Corrosion Engineers (NACE) Subcommittee on Conservation of Metallic Historic and Artistic Works. Copies are available from NACE, P.O. Box 218340, Houston, TX 77218.