Which impact categories have been identified as most important for a LEED project to accomplish?

The LEED rating system is designed to address the most important environmental impacts and human benefits of green building. The impact categories are based on the U.S. Environmental Protection Agency’s TRACI method (Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts), which evaluates the potential environmental effects of a product or process over its life cycle. The impact categories are: reverse contribution to global climate change; enhance individual human health and well-being; protect and restore water resources; protect, enhance and restore biodiversity and ecosystem services; promote sustainable and regenerative material cycles; build a greener economy; enhance social equity, environmental justice, community health and quality of life. Among these categories, reducing contribution to climate change and enhancing human health and well-being have been identified as the most important ones for a LEED project to accomplish. References: LEED v4 Green Associate Candidate Handbook, LEED v4 BD+C Reference Guide