Cottonwood Environmental Law Center v. United States Forest Service presents a troubling development for environmental plaintiffs seeking injunctive relief for procedural violations of the Endangered Species Act. The panel majority overturned a thirty-year-old presumption of irreparable harm, in a move that undermines the precautionary purpose of the Endangered Species Act. This Note first describes the relevant parts of the Act for understanding the Cottonwood case and its consequences and then provides a summary of the Cottonwood decision and its departure from Ninth Circuit precedent. Next, this Note explains how the Endangered Species Act mandates a precautionary approach and how the prior presumption of irreparable harm was more consistent with the Act’s precautionary purpose than the new standard, which requires plaintiffs to show irreparable harm to justify injunctive relief. Finally, this Note explains that the practical consequences of this decision will be to increase the barrier to injunctive relief for plaintiffs that lack the funding and expertise to establish irreparable harm, and to place district courts in the uneasy position of weighing more technical scientific information.