Green Star assesses the sustainable design, construction and operation of buildings, fitouts and communities. There are four Green Star rating tools available for certification of design, construction and operation of buildings, fitouts and communities. The tools cover a broad range of sustainable topics including energy and emissions and provide an overall rating, with 4-stars meaning “best practice, 5-star meaning Australian excellence and 6-star meaning international excellence. The program is voluntary and covers the residential, office, retail, accommodation, education and public buildings