Abstract: Twenty-five years used to seem like an exceedingly long time. It certainly did when I was graduating from law school and not yet twenty-five. My perspective on time, however, has (naturally) since evolved, much as environmental law itself and the controversies surrounding it have, too, evolved. The contrast between environmental law twenty-five years ago and environmental law today is remarkable and makes clear that environmental law and lawmaking were changing in fundamental ways a generation ago, but those changes are revealed only now with the aid of hindsight. To be sure, the statutory texts of domestic environmental law are strikingly the same. And yet, it is that static quality that ironically underscores how much has changed. A generation ago, environmental law scholars would routinely comment on how the only constant in environmental law was change: its dynamic nature. Congress was regularly passing significant statutory amendments in what was largely a constructive iterative lawmaking process, involving federal and state legislatures, agencies, and courts. Some might have worried that the change was too great—making it too difficult for the regulated community to adjust and invest. Whether any such concern then was justified, the concern now is quite different: too little change rather than too much. And the static nature of environmental lawmaking here in the United States stands in sharp contrast to the dynamic nature of environmental lawmaking globally. The United States, once a lauded pioneer, now very much risks being left behind. This essay is written in celebration of the 25th Annual Meeting of the National Association of Environmental Law Societies at the University of Michigan Law School and in recognition of Michigan Law’s hosting of the Association’s inaugural meeting in 1988. The essay focuses on three topics in reflecting on the changes in environmental law and environmental lawmaking since the Association’s first meeting. The first is Congress and the politics of environmental law. The second topic concerns the courts and the changing relationship of constitutional law to environmental law. And, finally, the essay considers the contrasting nature of the challenges that environmental lawyers and environmental law face today as compared to twenty-five years ago.