This report supports the launch of a UN Environment Programme World Conservation Monitoring Centre (UNEP-WCMC) project, in partnership with the Luc Hoffmann Institute (LHI) and other stakeholders and supported by the Swiss Federal Office for the Environment (FOEN), on developing and testing a Multidimensional Biodiversity Index (MBI) to measure biodiversity health. We define biodiversity health as a new concept that combines stocks of nature and flows of biodiversity to people and that considers biodiversity as a multidimensional socio-ecological concept. The MBI project aims to develop a policy-focused index for biodiversity health as a tool for decision makers to monitor if we are living within the regenerative capacity of nature, or whether we are piling up ecological debt for future generations, and therefore eroding our own opportunities to achieve sustainable development.