In order to assist discussions within the Partnership on Supply and Storage, important terms with relevance to storage of elemental mercury and to storage and disposal of waste consisting of el-emental mercury and waste containing or contaminated with mercury have been identified. These are presented in the format of a “Question and Answer” (Q & A) to provide a basic over-view. This document is for information only. Descriptions and definitions presented for various terms are not intended to pre-empt any discussions or decisions to be undertaken at upcoming mercury Intergovernmental Negotiating Committee sessions. Nevertheless, the document may serve as a basis for starting discussions.