||Currently, the top priority is given to building energy conservation and low-energy buildings during the building design process. Energy consumption has increased considerably these days, and the building sector is the largest energy consumer. In order to reduce building energy consumption and greenhouse gas emissions, green building certification and rating systems are required; these systems will encourage the development of energy efficient buildings. Most of the developed countries have already designed their own codes, systems, and regulations to promote energy conservation and reduce greenhouse gas emissions. Among the various green building certification systems, we selected and researched the LEED green building rating system, because it is the most widely used system in North America, South America, the Middle East, and East Asian countries. LEED 2009 (Version 3), the latest version, was released on April 27, 2009. We compared this version with the old versions with respect to the changed scores, credits, and assessment methods. Moreover, we focused on “IEQ Credit 8: Daylight & Views” because this credit is the most changed option in the LEED history. We analyzed the various daylighting assessment tools and codes in LEED 2009 and the associated problems and introduced new daylighting assessment tools. We hope that the new green building criteria and daylighting assessment tools will enable architects and engineers to develop better sustainable designs and will ensure that they employ daylighting strategies during building design process for energy conservation and green building certification.