SCALIA, J., announced the judgment of the Court and delivered the opinion of the Court with respect to Parts I, II, III-A, and IV, in which RENQUIST, C. J., and WHITE, KENNEDY, SOUTER, and THOMAS, JJ., joined

Justice SCALIA delivered the opinion of the Court with respect to Parts I, II, III-A, and IV, and an opinion with respect to Part III-B, in which The CHIEF JUSTICE, Justice WHITE, and Justice THOMAS join.

[1] This case involves a challenge to a rule promulgated by the Secretary of the Interior interpreting § 7 of the Endangered Species Act of 1973 (ESA), 87 Stat. 892, as amended, 16 U. S. C. § 1536, in such fashion as to render it applicable only to actions within the United States or on the high seas. The preliminary issue, and the only one we reach, is whether respondents here, plaintiffs below, have standing to seek judicial review of the rule.

I

[2] The ESA, 87 Stat. 884, as amended, 16 U. S. C. § 1531 et seq., seeks to protect species of animals against threats to their continuing existence caused by man. See generally TVA v. Hill, 437 U. S. 153 (1978). The ESA instructs the Secretary of the Interior to promulgate by regulation a list of those species which are either endangered or threatened under enumerated criteria, and to define the critical habitat of these species. 16 U. S. C. §§ 1533, 1536. Section 7(a)(2) of the Act then provides, in pertinent part:

[3] “Each Federal agency shall, in consultation with and with the assistance of the Secretary [of the Interior], insure that any action authorized, funded, or carried out by such agency . . . is not likely to jeopardize the continued existence of any endangered species or threatened species or result in the destruction or adverse modification of habitat of such species which is determined by the Secretary, after consultation as appropriate with affected States, to be critical.” 16 U. S. C. § 1536(a)(2).

[4] In 1978, the Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS), on behalf of the Secretary of the Interior and the Secretary of Commerce respectively, promulgated a joint regulation stating that the obligations imposed by § 7(a)(2) extend to actions taken in foreign nations. 43 Fed. Reg. 874 (1978). The next year, however, the Interior Department began to reexamine its position. A revised joint regulation, reinterpreting § 7(a)(2) to require consultation only for actions taken in the United States or on the high seas, was proposed in 1983.

[5] Shortly thereafter, respondents, organizations dedicated to wildlife conservation and other environmental causes, filed this action against the Secretary of the Interior, seeking a declaratory judgment that the new regulation is in error as to the geographic scope of § 7(a)(2) and an injunction requiring the Secretary to promulgate a new regulation restoring the initial interpretation.

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II

[6] Over the years, our cases have established that the irreducible constitutional minimum of standing contains three elements. First, the plaintiff must have suffered an “injury in fact”—an invasion of a legally protected interest which is (a) concrete and particularized, see id., at 756; Warth v. Seldin, 422 U. S. 490, 508 (1975); Sierra Club v. Morton, 405 U. S. 727, 740-741, n. 16 (1972);^[1] and (b) “actual or imminent, not `conjectural’ or `hypothetical,’ ” Whitmore, supra, at 155 (quoting Los Angeles v. Lyons, 461 U. S. 95, 102 (1983)). Second, there must be a causal connection between the injury and the conduct complained of—the injury has to be “fairly. . . trace[able] to the challenged action of the defendant, and not . . . th[e] result [of] the independent action of some third party not before the court.” Simon v. Eastern Ky. Welfare Rights Organization, 426 U. S. 26, 41-42 (1976). Third, it must be “likely,” as opposed to merely “speculative,” that the injury will be “redressed by a favorable decision.” Id., at 38, 43.

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[7] When the suit is one challenging the legality of government action or inaction, the nature and extent of facts that must be averred (at the summary judgment stage) or proved (at the trial stage) in order to establish standing depends considerably upon whether the plaintiff is himself an object of the action (or forgone action) at issue. If he is, there is ordinarily little question that the action or inaction has caused him injury, and that a judgment preventing or requiring the action will redress it. When, however, as in this case, a plaintiff’s asserted injury arises from the government’s allegedly unlawful regulation (or lack of regulation) of someone else, much more is needed. In that circumstance, causation and redressability ordinarily hinge on the response of the regulated (or regulable) third party to the government action or inaction—and perhaps on the response of others as well.

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[8] Thus, when the plaintiff is not himself the object of the government action or inaction he challenges, standing is not precluded, but it is ordinarily “substantially more difficult” to establish. Allen; Simon; Warth.

III

[9] We think the Court of Appeals failed to apply the foregoing principles in denying the Secretary’s motion for summary judgment. Respondents had not made the requisite demonstration of (at least) injury and redressability.

A

[10] Respondents’ claim to injury is that the lack of consultation with respect to certain funded activities abroad “increas[es] the rate of extinction of endangered and threatened species.” Of course, the desire to use or observe an animal species, even for purely esthetic purposes, is undeniably a cognizable interest for purpose of standing. See, e. g., Sierra Club v. Morton, 405 U. S., at 734. “But the `injury in fact’ test requires more than an injury to a cognizable interest. It requires that the party seeking review be himself among the injured.” To survive the Secretary’s summary judgment motion, respondents had to submit affidavits or other evidence showing, through specific facts, not only that listed species were in fact being threatened by funded activities abroad, but also that one or more of respondents’ members would thereby be “directly” affected apart from their “`special interest’ in th[e] subject.” 

[11] With respect to this aspect of the case, the Court of Appeals focused on the affidavits of two Defenders’ members— Joyce Kelly and Amy Skilbred. Ms. Kelly stated that she traveled to Egypt in 1986 and “observed the traditional habitat of the endangered nile crocodile there and intend[s] to do so again, and hope[s] to observe the crocodile directly,” and that she “will suffer harm in fact as the result of [the] American . . . role . . . in overseeing the rehabilitation of the Aswan High Dam on the Nile . . . and [in] develop[ing] . . . Egypt’s. . . Master Water Plan.” App. 101. Ms. Skilbred averred that she traveled to Sri Lanka in 1981 and “observed th[e] habitat” of “endangered species such as the Asian elephant and the leopard” at what is now the site of the Mahaweli project funded by the Agency for International Development (AID), although she “was unable to see any of the endangered species”; “this development project,” she continued, “will seriously reduce endangered, threatened, and endemic species habitat including areas that I visited . . . [, which] may severely shorten the future of these species”; that threat, she concluded, harmed her because she “intend[s] to return to Sri Lanka in the future and hope[s] to be more fortunate in spotting at least the endangered elephant and leopard.” When Ms. Skilbred was asked at a subsequent deposition if and when she had any plans to return to Sri Lanka, she reiterated that “I intend to go back to Sri Lanka,” but confessed that she had no current plans: “I don’t know [when]. There is a civil war going on right now. I don’t know. Not next year, I will say. In the future.”

[12] We shall assume for the sake of argument that these affidavits contain facts showing that certain agency-funded projects threaten listed species—though that is questionable. They plainly contain no facts, however, showing how damage to the species will produce “imminent” injury to Mses. Kelly and Skilbred. That the women “had visited” the areas of the projects before the projects commenced proves nothing. As we have said in a related context, “`Past exposure to illegal conduct does not in itself show a present case or controversy regarding injunctive relief . . . if unaccompanied by any continuing, present adverse effects.’ ” Lyons, 461 U. S., at 102 (quoting O’Shea v. Littleton, 414 U. S. 488, 495-496 (1974)). And the affiants’ profession of an “inten[t]” to return to the places they had visited before—where they will presumably, this time, be deprived of the opportunity to observe animals of the endangered species—is simply not enough. Such “some day” intentions—without any description of concrete plans, or indeed even any specification of when the some day will be—do not support a finding of the “actual or imminent” injury that our cases require.

[13] Besides relying upon the Kelly and Skilbred affidavits, respondents propose a series of novel standing theories. The first, inelegantly styled “ecosystem nexus,” proposes that any person who uses any part of a “contiguous ecosystem” adversely affected by a funded activity has standing even if the activity is located a great distance away. This approach, as the Court of Appeals correctly observed, is inconsistent with our opinion in National Wildlife Federation, which held that a plaintiff claiming injury from environmental damage must use the area affected by the challenged activity and not an area roughly “in the vicinity” of it. 497 U. S., at 887-889; see also Sierra Club, 405 U. S., at 735. It makes no difference that the general-purpose section of the ESA states that the Act was intended in part “to provide a means whereby the ecosystems upon which endangered species and threatened species depend may be conserved,” 16 U. S. C. § 1531(b). To say that the Act protects ecosystems is not to say that the Act creates (if it were possible) rights of action in persons who have not been injured in fact, that is, persons who use portions of an ecosystem not perceptibly affected by the unlawful action in question.

[14] Respondents’ other theories are called, alas, the “animal nexus” approach, whereby anyone who has an interest in studying or seeing the endangered animals anywhere on the globe has standing; and the “vocational nexus” approach, under which anyone with a professional interest in such animals can sue. Under these theories, anyone who goes to see Asian elephants in the Bronx Zoo, and anyone who is a keeper of Asian elephants in the Bronx Zoo, has standing to sue because the Director of the Agency for International Development (AID) did not consult with the Secretary regarding the AID-funded project in Sri Lanka. This is beyond all reason. Standing is not “an ingenious academic exercise in the conceivable,” United States v. Students Challenging Regulatory Agency Procedures (SCRAP), 412 U. S. 669, 688 (1973), but as we have said requires, at the summary judgment stage, a factual showing of perceptible harm. It is clear that the person who observes or works with a particular animal threatened by a federal decision is facing perceptible harm, since the very subject of his interest will no longer exist. It is even plausible—though it goes to the outermost limit of plausibility—to think that a person who observes or works with animals of a particular species in the very area of the world where that species is threatened by a federal decision is facing such harm, since some animals that might have been the subject of his interest will no longer exist, see Japan Whaling Assn. v. American Cetacean Society, 478 U. S. 221, 231, n. 4 (1986). It goes beyond the limit, however, and into pure speculation and fantasy, to say that anyone who observes or works with an endangered species, anywhere in the world, is appreciably harmed by a single project affecting some portion of that species with which he has no more specific connection.

B

[15] Besides failing to show injury, respondents failed to demonstrate redressability. Instead of attacking the separate decisions to fund particular projects allegedly causing them harm, respondents chose to challenge a more generalized level of Government action (rules regarding consultation), the invalidation of which would affect all overseas projects.

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[16] The most obvious problem in the present case is redressability. Since the agencies funding the projects were not parties to the case, the District Court could accord relief only against the Secretary: He could be ordered to revise his regulation to require consultation for foreign projects. But this would not remedy respondents’ alleged injury unless the funding agencies were bound by the Secretary’s regulation, which is very much an open question.

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[17] When the Secretary promulgated the regulation at issue here, he thought it was binding on the agencies, see 51 Fed. Reg. 19928 (1986). The Solicitor General, however, has repudiated that position here, and the agencies themselves apparently deny the Secretary’s authority.

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[18] The short of the matter is that redress of the only injury in fact respondents complain of requires action (termination of funding until consultation) by the individual funding agencies; and any relief the District Court could have provided in this suit against the Secretary was not likely to produce that action.

[19] A further impediment to redressability is the fact that the agencies generally supply only a fraction of the funding for a foreign project. AID, for example, has provided less than 10% of the funding for the Mahaweli project. Respondents have produced nothing to indicate that the projects they have named will either be suspended, or do less harm to listed species, if that fraction is eliminated. As in Simon, 426 U. S., at 43-44, it is entirely conjectural whether the nonagency activity that affects respondents will be altered or affected by the agency activity they seek to achieve. There is no standing.

IV

[20] The Court of Appeals found that respondents had standing for an additional reason: because they had suffered a “procedural injury.” The so-called “citizen-suit” provision of the ESA provides, in pertinent part, that “any person may commence a civil suit on his own behalf (A) to enjoin any person, including the United States and any other governmental instrumentality or agency . . . who is alleged to be in violation of any provision of this chapter.”

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[21] To understand the remarkable nature of this holding one must be clear about what it does not rest upon: This is not a case where plaintiffs are seeking to enforce a procedural requirement the disregard of which could impair a separate concrete interest of theirs (e. g., the procedural requirement for a hearing prior to denial of their license application, or the procedural requirement for an environmental impact statement before a federal facility is constructed next door to them).^[7] Nor is it simply a case where concrete injury has been suffered by many persons, as in mass fraud or mass tort situations. Nor, finally, is it the unusual case in which Congress has created a concrete private interest in the outcome of a suit against a private party for the Government’s benefit, by providing a cash bounty for the victorious plaintiff. Rather, the court held that the injury-in-fact requirement had been satisfied by congressional conferral upon all persons of an abstract, selfcontained, noninstrumental “right” to have the Executive observe the procedures required by law. We reject this view.

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[22] Whether the courts were to act on their own, or at the invitation of Congress, in ignoring the concrete injury requirement described in our cases, they would be discarding a principle fundamental to the separate and distinct constitutional role of the Third Branch—one of the essential elements that identifies those “Cases” and “Controversies” that are the business of the courts rather than of the political branches. “The province of the court,” as Chief Justice Marshall said in Marbury v. Madison, 1 Cranch 137, 170 (1803), “is, solely, to decide on the rights of individuals.” Vindicating the public interest (including the public interest in Government observance of the Constitution and laws) is the function of Congress and the Chief Executive. The question presented here is whether the public interest in proper administration of the laws (specifically, in agencies’ observance of a particular, statutorily prescribed procedure) can be converted into an individual right by a statute that denominates it as such, and that permits all citizens (or, for that matter, a subclass of citizens who suffer no distinctive concrete harm) to sue. If the concrete injury requirement has the separation-ofpowers significance we have always said, the answer must be obvious: To permit Congress to convert the undifferentiated public interest in executive officers’ compliance with the law into an “individual right” vindicable in the courts is to permit Congress to transfer from the President to the courts the Chief Executive’s most important constitutional duty, to “take Care that the Laws be faithfully executed,” Art. II, § 3. It would enable the courts, with the permission of Congress, “to assume a position of authority over the governmental acts of another and co-equal department,” Massachusetts v. Mellon, 262 U. S., at 489, and to become “`virtually continuing monitors of the wisdom and soundness of Executive action.’ ”

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[23] We hold that respondents lack standing to bring this action and that the Court of Appeals erred in denying the summary judgment motion filed by the United States. The opinion of the Court of Appeals is hereby reversed, and the cause is remanded for proceedings consistent with this opinion.

[24] It is so ordered.

Justice KENNEDY, with whom Justice SOUTER joins, concurring in part and concurring in the judgment.

[1] Although I agree with the essential parts of the Court’s analysis, I write separately to make several observations.

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[2] While it may seem trivial to require that Mses. Kelly and Skilbred acquire airline tickets to the project sites or announce a date certain upon which they will return, this is not a case where it is reasonable to assume that the affiants will be using the sites on a regular basis, see Sierra Club v. Morton, supra, at 735, n. 8, nor do the affiants claim to have visited the sites since the projects commenced. With respect to the Court’s discussion of respondents’ “ecosystem nexus,” “animal nexus,” and “vocational nexus” theories, I agree that on this record respondents’ showing is insufficient to establish standing on any of these bases. I am not willing to foreclose the possibility, however, that in different circumstances a nexus theory similar to those proffered here might support a claim to standing. See Japan Whaling Assn. v. American Cetacean Society, 478 U. S. 221, 231, n. 4 (1986) (“[R]espondents . . . undoubtedly have alleged a sufficient `injury in fact’ in that the whale watching and studying of their members will be adversely affected by continued whale harvesting”).

[3] In light of the conclusion that respondents have not demonstrated a concrete injury here sufficient to support standing under our precedents, I would not reach the issue of redressability that is discussed by the plurality in Part III—B.

[4] I also join Part IV of the Court’s opinion with the following observations. As Government programs and policies become more complex and far reaching, we must be sensitive to the articulation of new rights of action that do not have clear analogs in our common-law tradition. Modern litigation has progressed far from the paradigm of Marbury suing Madison to get his commission, Marbury v. Madison, 1 Cranch 137 (1803), or Ogden seeking an injunction to halt Gibbons’ steamboat operations, Gibbons v. Ogden, 9 Wheat. 1 (1824). In my view, Congress has the power to define injuries and articulate chains of causation that will give rise to a case or controversy where none existed before, and I do not read the Court’s opinion to suggest a contrary view. See Warth v. Seldin, 422 U. S. 490, 500 (1975). In exercising this power, however, Congress must at the very least identify the injury it seeks to vindicate and relate the injury to the class of persons entitled to bring suit. The citizen-suit provision of the Endangered Species Act does not meet these minimal requirements, because while the statute purports to confer a right on “any person . . . to enjoin . . . the United States and any other governmental instrumentality or agency . . . who is alleged to be in violation of any provision of this chapter,” it does not of its own force establish that there is an injury in “any person” by virtue of any “violation.” 16 U. S. C. § 1540(g)(1)(A).

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[5] While it does not matter how many persons have been injured by the challenged action, the party bringing suit must show that the action injures him in a concrete and personal way. This requirement is not just an empty formality. It preserves the vitality of the adversarial process by assuring both that the parties before the court have an actual, as opposed to professed, stake in the outcome, and that “the legal questions presented . . . will be resolved, not in the rarified atmosphere of a debating society, but in a concrete factual context conducive to a realistic appreciation of the consequences of judicial action.” Valley Forge Christian College v. Americans United for Separation of Church and State, Inc., 454 U. S. 464, 472 (1982). In addition, the requirement of concrete injury confines the Judicial Branch to its proper, limited role in the constitutional framework of Government.

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Justice BLACKMUN, with whom Justice O’CONNOR joins, dissenting.

[1] I part company with the Court in this case in two respects. First, I believe that respondents have raised genuine issues of fact—sufficient to survive summary judgment—both as to injury and as to redressability. Second, I question the Court’s breadth of language in rejecting standing for “procedural” injuries. I fear the Court seeks to impose fresh limitations on the constitutional authority of Congress to allow citizen suits in the federal courts for injuries deemed “procedural” in nature. I dissent.

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1

[2] Were the Court to apply the proper standard for summary judgment, I believe it would conclude that the sworn affidavits and deposition testimony of Joyce Kelly and Amy Skilbred advance sufficient facts to create a genuine issue for trial concerning whether one or both would be imminently harmed by the Aswan and Mahaweli projects. In the first instance, as the Court itself concedes, the affidavits contained facts making it at least “questionable” (and therefore within the province of the factfinder) that certain agencyfunded projects threaten listed species. The only remaining issue, then, is whether Kelly and Skilbred have shown that they personally would suffer imminent harm.

[3] I think a reasonable finder of fact could conclude from the information in the affidavits and deposition testimony that either Kelly or Skilbred will soon return to the project sites, thereby satisfying the “actual or imminent” injury standard. The Court dismisses Kelly’s and Skilbred’s general statements that they intended to revisit the project sites as “simply not enough.”  But those statements did not stand alone. A reasonable finder of fact could conclude, based not only upon their statements of intent to return, but upon their past visits to the project sites, as well as their professional backgrounds, that it was likely that Kelly and Skilbred would make a return trip to the project areas.

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[4] By requiring a “description of concrete plans” or “specification of when the some day [for a return visit] will be,” the Court, in my view, demands what is likely an empty formality. No substantial barriers prevent Kelly or Skilbred from simply purchasing plane tickets to return to the Aswan and Mahaweli projects. This case differs from other cases in which the imminence of harm turned largely on the affirmative actions of third parties beyond a plaintiff’s control.

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[5] To be sure, a plaintiff’s unilateral control over his or her exposure to harm does not necessarily render the harm nonspeculative. Nevertheless, it suggests that a finder of fact would be far more likely to conclude the harm is actual or imminent, especially if given an opportunity to hear testimony and determine credibility.

[6] I fear the Court’s demand for detailed descriptions of future conduct will do little to weed out those who are genuinely harmed from those who are not. More likely, it will resurrect a code-pleading formalism in federal court summary judgment practice, as federal courts, newly doubting their jurisdiction, will demand more and more particularized showings of future harm. Just to survive summary judgment, for example, a property owner claiming a decline in the value of his property from governmental action might have to specify the exact date he intends to sell his property and show that there is a market for the property, lest it be surmised he might not sell again. A nurse turned down for a job on grounds of her race had better be prepared to show on what date she was prepared to start work, that she had arranged daycare for her child, and that she would not have accepted work at another hospital instead. And a Federal Tort Claims Act plaintiff alleging loss of consortium should make sure to furnish this Court with a “description of concrete plans” for her nightly schedule of attempted activities.

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[7] The Court expresses concern that allowing judicial enforcement of “agencies’ observance of a particular, statutorily prescribed procedure” would “transfer from the President to the courts the Chief Executive’s most important constitutional duty, to `take Care that the Laws be faithfully executed,’ Art. II, § 3.”  In fact, the principal effect of foreclosing judicial enforcement of such procedures is to transfer power into the hands of the Executive at the expense—not of the courts—but of Congress, from which that power originates and emanates.

[8] Under the Court’s anachronistically formal view of the separation of powers, Congress legislates pure, substantive mandates and has no business structuring the procedural manner in which the Executive implements these mandates. To be sure, in the ordinary course, Congress does legislate in black-and-white terms of affirmative commands or negative prohibitions on the conduct of officers of the Executive Branch. In complex regulatory areas, however, Congress often legislates, as it were, in procedural shades of gray. That is, itsets forth substantive policy goals and provides for their attainment by requiring Executive Branch officials to follow certain procedures, for example, in the form of reporting, consultation, and certification requirements.

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[9] The consultation requirement of § 7 of the Endangered Species Act is a similar, action-forcing statute. Consultation is designed as an integral check on federal agency action, ensuring that such action does not go forward without full consideration of its effects on listed species.

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[10] Congress legislates in procedural shades of gray not to aggrandize its own power but to allow maximum Executive discretion in the attainment of Congress’ legislative goals.

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[11] The Court never has questioned Congress’ authority to impose such procedural constraints on Executive power. Just as Congress does not violate separation of powers by structuring the procedural manner in which the Executive shall carry out the laws, surely the federal courts do not violate separation of powers when, at the very instruction and command of Congress, they enforce these procedures.

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III

[12] In conclusion, I cannot join the Court on what amounts to a slash-and-burn expedition through the law of environmental standing. In my view, “[t]he very essence of civil liberty certainly consists in the right of every individual to claim the protection of the laws, whenever he receives an injury.”

[13] I dissent.