ESA (Endangered Species Act) has been one of the more contentious environmental laws. This may stem from its strict substantive provisions, which can affect the use of both federal and non-federal lands and resources. Under ESA, species of plants and animals (both vertebrate and invertebrate) can be listed as endangered or threatened according to assessments of their risk of extinction. Once a species is listed, powerful legal tools are available to aid its recovery and protect its habitat. ESA may also be controversial because dwindling species are usually harbingers of broader ecosystem decline: the most common cause of species listing is habitat loss. Major issues in recent years have included the role of science in decision-making, critical habitat (CH) designation and procedures, protection by and incentives for property owners, and appropriate protection of listed species, among others. This new book presents the latest updates on the ESA and its impact.