Abstract: This comprehensive examination of U.S. law as it relates to climate change completely updates and reconsiders material from the prior editions while also adding extensive new material. It offers an increased emphasis on all aspects of energy regulation, as well as additional material on emerging issues such as adaptation and geoengineering. The legal landscape around climate change is complex, unstable, and expanding. Scientists continue to publish new findings, policy makers regularly adopt new regulations, and petitioners file new litigation, nationwide and around the world. Hence the need for this third edition. Most of it is completely new, and the few chapters carried over from the second edition have been thoroughly updated.