Green building certification systems are a set of rating systems and tools that are used to assess a building or a construction project's performance from a sustainability and environmental perspective. Such ratings aim to improve the overall quality of buildings and infrastructures, integrate a life cycle approach in its design and construction, and promote the fulfillment of the United Nations Sustainable Development Goals by the construction industry. Buildings that have been assessed and are deemed to meet a certain level of performance and quality, receive a certificate proving this achievement. According to the Global Status Report 2017 published by United Nations Environment Programme (UNEP) in coordination with the International Energy Agency (IEA), buildings and construction activities together contribute to 36% of the global energy use and 39% of carbon dioxide () emissions. Through certification, the associated environmental impacts during the lifecycle of buildings and other infrastructures (typically design, construction, operation and maintenance) could be better understood and mitigated. Currently, more than 100 building certifications systems exist around the world. The most popular building certification models today are BREEAM (UK), LEED (US), and DGNB (Germany). History In the mid-1980s, environmental issues were in the news and public attention due to different international disasters such as the Bhopal disaster (1984), Chernobyl nuclear explosion (1986) and the Exxon Valdez tanker spill (1989). Lifecycle assessments (LCAs) were starting to gain traction from its initial stages in the 1970s to the 1980s and it was in 1991 that the term was first coined. With increasing cognizance of environmental impacts due to human activities, a more comprehensive assessment of buildings utilizing the principles of LCA was much sought after. In 1990, the first Sustainability Assessment Method for buildings, BREEAM was released. In 1993, Rick Fedrizzi, David Gottfried and Mike Italiano formed the world's first Green Building Council (GBC) with the U.S. Green Building Council. Their mission was to promote sustainability-focused practices in the building and construction industry and advance sustainable building principles. USGBC was further responsible for the creation of the Leadership in Energy and Environmental Design (LEED) green building rating system in 1998. The integration of energy usage, materials performance and other building-related environmental issues, along with an aim towards standardizing the comparison of assessments led to more comprehensive building assessment methods. With the principles of green building gaining momentum, several more GBCs were established across the world. In 2002, the World Green Building Council