The Higg Index is an open-source three-piece set of product tools developed by the Sustainable Apparel Coalition (SAC), which enables businesses to measure and score their sustainability performance. 1. Product Tools allow their users to measure impact at the product level; 2. Facility Tools measure environmental and social sustainability at manufacturing facilities; and 3. Brand and Retail Tools measure environmental and social impact across the value chain.(1) Among these, the most widely adopted tool is the Higg Materials Sustainability Index (Higg MSI), a cradle-to-gate scoring methodology that helps measure material impacts across five key areas: climate change, eutrophication, fossil fuels resource depletion, water scarcity, and chemicals. Each material, from cotton to leather, is assigned a points-based score according to raw material source, yarn and textile formation, preparation and coloration.(2) The Higg MSI scoring methodology is based on life cycle assessment (LCA) data and weighted also on how commonly materials are used; this means that for example cotton will have a heavier weighting than cashmere.(3)