The CDA boasts 911 Leadership in Energy and Environmental Design (LEED) certified buildings at O’Hare and Midway International Airports. The LEED certification, bestowed by the U.S. Green Building Council (USGBC), indicates that a structure has achieved a requisite level of sustainability, resource efficiency, energy efficiency and environmental quality. Projects are awarded points for incorporating sustainable technologies and USGBC aims to help building owners and operators be environmentally responsible and use resources efficiently.