For several decades, courts have approached citizen suits with judicially created rules for standing. These requirements for standing have been vague and unworkable, and often serve merely as a screening mechanism for docket management. The use of standing rules to screen cases, in turn, yields inconsistent decisions and tribunal splits along partisan lines, suggesting that courts are using these rules in citizen suits as a proxy for the merits. Numerous commentators, and some Supreme Court Justices, have therefore suggested that Congress could, or should, provide legislative guidelines for standing. This Article takes the suggestion a step further, and argues that Congress has implicitly delegated the matter to the administrative agencies with primary enforcement authority over the subject matter. Courts regularly allow agencies to fill gaps in their respective statutes, meaning congressional silence on a point often constitutes discretionary leeway for the agency charged with implementation of the statute. Agencies already have explicit statutory authority to preempt citizen suits or define violations for which parties may sue. The existing statutory framework therefore suggests agencies could promulgate rules for the injury-in-fact and causation prongs of standing in citizen suits. Moreover, agencies have an advantage over courts in terms of expertise about the harms involved and which suits best represent the public interest. On the more delicate question of citizen suits against agencies themselves, agencies could default to the “special solicitude for states” rule illustrated in Massachusetts v. EPA. Finally, this Article explains how standing can function as a beneficial channeling tool rather than an awkward screening device, by allowing agencies to align citizen suits more closely with the larger public interest and established policy goals.