The Green Star South Africa rating tool is an objective measurement for green buildings with a focus on energy. Building owners have to submit the relevant building data to the Green Building Council South Africa (GBCSA). Afterwards, an independent assessor evaluates the building and its green measures and rates it. The building owner then receives a certification with a 4-Star, 5-Star or 6-Star rating. 4 Star means “Best practice”, 5 Star stands for “South African Excellence” and 6 Star means “World Leadership”. Several rating tools were implemented to reflect different market sectors including a rating tool for offices, retail centres, multi-unit residential buildings as well as public & education buildings.