This article surveys and analyses trends in the astonishing arena of environmental citizen suits. Environmental citizen suits matter. Borne in a fulcrum of necessity due to inadequate resources and resolve, and borrowing a bit from common law qui tam without the bounty, Congress has experimented by providing citizens the remarkable authority to file federal lawsuits as “private attorneys general” to enforce many of the nation's environmental laws. And enforce they do. Despite ever more cascading burdens respecting notice, jurisdiction, preclusion, actions against EPA and third parties, remedies, SEPs and attorney fees, there are more reported environmental citizen suits than ever. On average, citizens send more than one notice of intent to sue a day, and file more than one lawsuit a week. These efforts help advance the rule of law and keep agencies honest. But there are signs citizen suits are needed now more than ever. EPA is referring fewer cases to DOJ. Trend data shows EPA civil judicial settlement, the value of injunctive relief, judicial and administrative penalties, and SEP values are in overall decline. Even without these considerations, environmental enforcement is losing ground. This article concludes by explaining the need and worth of environmental citizen suits.