Green Star, NABERS, and LEED are all sustainability rating systems that are used to assess the environmental performance of buildings. Green Star certification is an Australian-specific rating system that focuses on overall sustainability performance and covers new construction and major renovations. NABERS, also Australian, primarily evaluates the operational performance of existing buildings.   LEED is an international system that applies to various countries and building types. Green Star and LEED have different rating levels and use a points-based system, while NABERS uses a star rating scale based on actual consumption data. Green Star and NABERS consider local priorities, while LEED offers regional adaptations. Each system aims to promote sustainability in the built environment, but their scope, geographical focus, and assessment methodologies differ.