The mining sector plays a key critical role in the economic and social development of resource-rich developing countries. With a responsible and sustainable mining sector, countries can attract investment, generating tax revenue and other benefits to help reduce poverty and meet climate and Sustainable Development Goals. To achieve this, governments need to understand how effectively their mining sector is managed compared to internationally accepted good practice. The Mining Sector Diagnostic tool is a data-driven, evidence-based assessment that identifies target areas for potential reform.