This chapter describes how the field of environmental law is organized and the way it operates. It looks at how several major environmental laws illustrate strategic choices in creating environmental law and policy. The government's role with regard to the environment was to hand out land—including that taken by force, fraud, or coercion from native peoples—and encourages development. Human societies are utterly dependent on the natural environment. From the food they grow to the water they drink to the air they breathe, without a healthy environment, human societies cannot function. The journey of the plaintiffs in the case of Juliana v. United States is in early stages, but it represents a growing interest in redefining environmental law and policy around a fundamental, constitutional right to a healthy environment. The Clean Air Act is one of the United States' most important environmental statutes, and it promises to continue to play an important role in the future of environmental law.