The Metrics of Sustainable Diets and Food Systems project is a multi-institutional initiative realized in partnership by Bioversity International and CIHEAM-Montpellier (2013-2014) that aims at exploring the different approaches to the assessment of sustainability of diets and food systems, establishing a multidisciplinary taskforce of experts and identifying a shortlist of indicators for sustainable diets and food systems to inform policy-makers. The initial focus was on the Mediterranean region. The research approach builds on the assumptions that sustainability assessment aims at capturing the ability of a system to maintain and enhance its essential functions over time, and that sustainability addresses threats to preserving life support systems, including their capacity to withstand and adjust.