Recognizing the non-ferrous metals sector was estimated to be a major source of mercury emissions and releases, the Partnership Advisory Group (PAG) decided at its tenth meeting (Geneva, 23 November 2019) to initiate work on the topic. In follow up to expert consultations in April 2020, Partnership area leads agreed to guide a process for developing a study report, with the aim to better understand the mercury mass balance globally between supply, storage, and waste treatment related to non-ferrous metals mining and smelting operations. As per the leads guidance, the report could also include a review of existing knowledge and information gaps concerning mercury volumes from different stages of the processes; a showcase of the different methods currently in use for reducing mercury releases and disposing mercury at different key stages of the processes, highlighting best practices, including methods of detection and monitoring of mercury releases along the processes; and potential ideas for further research and cooperation, including opportunities for capacity development.