For several decades, courts have approached citizen suits with judicially created rules for standing. These rules are vague and unworkable, often serving 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. Many have suggested that Congress could, or should, provide 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, so Congress’s silence on a point often constitutes discretionary leeway for the agency. Agencies already have explicit statutory authority to preempt citizen suits or define violations for which parties may sue; the existing statutory framework therefore suggests that agencies could promulgate rules for standing in citizen suits. Moreover, agencies have an advantage over courts in terms of expertise about which suits best represent the public interest. Further, for suits against the agencies themselves, agencies could default to the “special solicitude for states” rule. Finally, this Article explains how standing can function as a beneficial channeling tool rather than an ad hoc screening device, by allowing agencies to align citizen suits more closely with the larger public interest.