This is an introductory chapter to a more extended study of compliance with international treaty obligations. The research has been supported by grants from the Pew Charitable Trust and the Carnegie Corporation of New York, for which we wish to express our gratitude. Earlier versions of this article were presented at seminars at the Kennedy School of Government, Harvard University, and at the University of Chicago Law School. Robert Keohane has been particularly helpful in commenting on the earlier efforts. Our thanks are also due to our many student research assistants and especially to Sean Cote, Fred Jacobs, and Jan Martinez, who labored on the references.

¹ Carter, Barry E. and Trimble, Phillip R., International Law (Boston: Little, Brown, 1991), pp. 133–252Google Scholar, cite a statistical study showing that of 10, 189 U.S. treaties and international agreements made between 1789 and 1979, 8, 955 were concluded between 1933 and 1979 (see p. 169). In the U.S. lexicon, the term “treaty” is reserved for international agreements ratified with the advice and consent of the Senate in accordance with Article 2, cl. 2 of the Constitution. Other international agreements are concluded by the President, in the great majority of cases with the authorization of Congress and less frequently on his or her own responsibility. All of these are “treaties” according to international usage, which defines a treaty as “an international agreement, concluded between states in written form and governed by international law.” See Vienna Convention on the Law of Treaties (entered into force on 27 January 1980) Article 2(l)(a), in International Legal Materials, vol. 8 (Washington, D.C.: The American Society of International Law, 07 1969), pp. 679–735Google Scholar (hereafter cited as Vienna Convention on the Law of Treaties). The quotation is found on p. 701. The computer bank of the United Nations (UN) Treaty Office shows treaty growth, including multilateral and bilateral treaties and amendments, as follows: 373 treaties were entered into during the ten-year period ending in 1955; 498 in the period ending in 1965; 808 in the period ending in 1975; 461 in the period ending in 1985; and 915 in the period ending in 1991.

² Treaty law, based on nineteenth-century practice, adopts, implicitly or explicitly, a contractual model of bilateral relationships (or, at most, agreements among a few parties), and a good deal of contemporary work in international relations reflects this same framework. Although nineteenth century legal thought was hospitable to conceptions based on contract, they do not fit comfortably with regulatory lawmaking.

³ We are mindful of the distinction between treaty compliance and regime effectiveness. See Young, Oran, The Effectiveness of International Institutions: Hard Cases and Critical Variables, in Rosenau, James N. and Czempiel, Ernst-Otto, eds., Governance Without Government: Order and Change in World Politics (Cambridge: Cambridge University Press, 1992), pp. 160–92CrossRefGoogle Scholar; and Ausubel, Jesse and Victor, David, “Verification of International Environmental Agreements,” Annual Review of Energy and Environment, vol. 17, 1992, pp. 1–43CrossRefGoogle Scholar. The parties to the International Whaling Convention, for example, complied fully with the quotas set by its commission, but the, whale population crashed because the quotas were too high. Nevertheless, we think the observance (or not) of treaty commitments by the parties is a subject worth studying in its own right. Moreover, treaties are ordinarily intended to induce behavior that is expected to ameliorate the problem to which they are directed, so that, if Young's warning is kept in mind, compliance may be a fair first approximation surrogate for effectiveness.

⁴ See Henkin, Louis, How Nations Behave, 2d ed (New York: Columbia University Press, 1979), p. 47; and p. 69Google Scholar of Henkin, Louis, “International Law: Politics, Values, and Functions: General Course on Public International Law,” Recueil Des Cours, vol. 216, 1989, pp. 1–416Google Scholar, emphasis original.

⁵ Machiavelli, Niccolò, The Prince, eds. Skinner, Quentin and Price, Russell (Cambridge: Cambridge University Press, 1988), pp. 61–62Google Scholar. For a modern instance, see Morgenthau, Hans J., Politics Among Nations: The Struggle for Power and Peace, 5th ed. (New York: Alfred A. Knopf, 1978), p. 560Google Scholar; “In my experience [states] will keep their bargains as long as it is in their interest.”

⁶ See, for example, Caporaso, James A., “International Relations Theory and Multilateralism: The Search for Foundations,” International Organization 46 (Summer 1992), pp. 599–632CrossRefGoogle Scholar.

⁷ Schelling, Thomas C., The Strategy of Conflict (Cambridge, Mass.: Harvard University Press, 1980), p. 4Google Scholar.

⁸ Young, Oran R., Compliance and Public Authority: A Theory with International Applications (Baltimore, Md.: Johns Hopkins University Press, 1979), pp. 31–34Google Scholar.

⁹ See Stigler, George, “The Economics of Information,” Journal of Political Economy 69 (June 1961), pp. 213–25CrossRefGoogle Scholar; Stigler, G. J. and Becker, G. S., “De Gustibus non Est Disputandum” (There is no disputing taste), in Cook, Karen S. and Levi, Margaret, eds., The Limits of Rationality (Chicago: University of Chicago Press, 1990), pp. 191–216Google Scholar; Lindblom, Charles E., The Policy Making Process (Englewood Cliffs, N.J.: Prentice-Hall, 1968), p. 14Google Scholar; and Young, , Compliance and Public Authority, pp. 16–17Google Scholar.

¹⁰ Simon, Herbert, Models of Man: Social and Rational-Mathematical Essays on Rational Human Behavior in a Social Setting (New York: John Wiley & Sons, 1957), pp. 200–204Google Scholar. See also March, James G. and Simon, Herbert A., Organizations (New York: John Wiley & Sons, 1958), p. 169Google Scholar. For an example of this model of organizational behavior applied to the analysis of international affairs, see Allison, Graham T., The Essence of Decision: Explaining the Cuban Missile Crisis (Glen view, III.: Scott, Foreman, 1971), chaps. 3 and 4Google Scholar.

¹¹ Rheinstein, M., ed., Max Weber on Law in Economy and Society (New York: Simon and Schuster, 1954), p. 350Google Scholar; “For modern bureaucracy, the element of ‘calculability of its rules’ has really been of decisive significance.”

¹² Even in the case of peace treaties, the victor seems to attach importance to the signature of the vanquished on the document. After the Persian Gulf War, for example, the UN Security Council insisted that Iraq accept the terms of Resolution 687 establishing a cease-fire. See Cote, Sean, A Narrative of the Implementation of Section C of UN Security Council Resolution 687, Occasional Paper, Center for Science and International Affairs, Harvard University, Cambridge, Mass., forthcomingGoogle Scholar; and Morgenthau, , Politics Among Nations, p. 282Google Scholar.

¹³ Trimble, Phillip R., “Arms Control and International Negotiation Theory,” Stanford Journal of International Law 25 (Spring 1989), pp. 543–74, especially p. 549Google Scholar.

¹⁴ See Newhouse, John, Dawn, Cold: The Story of SALT (New York: Holt, Rinehart and Winston, 1973)Google Scholar; Smith, Gerard C., Double talk: The Story of SALT I (Lanham, Md.: University Press of America, 1985)Google Scholar; Talbott, Strobe, Endgame: The Inside Story of SALT II (New York: Harper & Row, 1979)Google Scholar; Talbott, Strobe, Deadly Gambits: The Reagan Administration and the Stalemate in Nuclear Arms Control (New York: Knopf, 1984)Google Scholar; Garthoff, Raymond L., Detente and Confrontation: American-Soviet Relations from Nixon to Reagan (Washington, D.C.: Brookings Institution, 1985)Google Scholar; and McNeill, J., “U.S.-U.S.S.R. Arms Negotiations: The Process and the Lawyer,” American Journal of International Law 79 (spring 1985), pp. 52–67CrossRefGoogle Scholar. Although knowledge of the process in the former Soviet Union is less detailed, the sources cited above, among others, suggest that (making allowances for a more compartmentalized bureaucratic structure) the process was not fundamentally dissimilar.

¹⁵ Benedick, Richard Elliot, Ozone Diplomacy: New Directions in Safeguarding the Planet (Cambridge, Mass: Harvard University Press, 1991), pp. 51–53Google Scholar. The Domestic Policy Council, which established a special senior-level working group to ride herd on the process, consists of nine Cabinet secretaries, the director for the OMB, and the USTR. At the time of the ozone negotiations, the council was chaired by Attorney General Edwin Meese. Other states, at least in advanced industrialized societies, exhibit similar, if perhaps not quite as baroque, internal practices in preparation for negotiations. Developing countries, with small resources to commit to bureaucratic coordination, may rely more on the judgment and inspiration of representatives on the scene.

¹⁶ Trimble, , “Arms Control and International Negotiation Theory,” p. 550Google Scholar.

¹⁷ See Benedick, , Ozone Diplomacy, p. 57Google Scholar, for a description of the emphasis on Congress, industry, and environmental groups in the development of the U.S. strategy to build support for the Protocol on Substances that Deplete the Ozone Layer. For a discussion of how governments “organize themselves to cope with the flow of business generated by international organizations” in an international political system of “complex interdependence,” see Keohane, Robert O. and Nye, Joseph S., Power and Interdependence, 2d ed (Glen view, III.: Scott, Foresman, 1989), p. 35Google Scholar.

¹⁸ Hudec uses the examples of the General Agreement on Tariffs and Trade (GATT) and the International Trade Organization (ITO): “For the better part of the first decade, GATT meetings resembled a reunion of the GATT/ITO draftsmen themselves. Failure of the code would have meant a personal failure to many of these officials, and violation of rules they had helped to write could not help being personally embarrassing.” See p. 1365 of Hudec, Robert E., “GATT or GABB? The Future Design of the General Agreement of Tariffs and Trade,” Yale Law Journal 80 (06 1971), pp. 1299–386CrossRefGoogle Scholar. See also Hudec, Robert E., The GATT Legal System and World Trade Diplomacy, 2d ed. (Salem, N. H.: Butterworth Legal Publishers, 1990), p. 54Google Scholar.

¹⁹ The Vienna Convention on the Law of Treaties permits limited recourse to the negotiating history when the treaty text is ambiguous, though the emphasis given to such history differs in various tribunals and national courts. See Vienna Convention on the Law of Treaties, Article 32. In the United States, resort to the negotiating history is much freer. See United States v. Stuart, 489 U.S. 353–377 (1989); and Vagts, Detlev F. “Senate Materials and Treaty Interpretation: Some Research Hints for the Supreme Court,” American Journal of International Law 83 (07 1989), pp. 546–50CrossRefGoogle Scholar.

²⁰ Putnam, Robert D., “Diplomacy and Domestic Politics: The Logic of Two-Level Games,” International Organization 42 (Summer 1988), pp. 427–60CrossRefGoogle Scholar.

²¹ See Sebenius, James K., Negotiating the Law of the Sea (Cambridge, Mass.: Harvard University Press, 1984)Google Scholar; and Wertenbaker, William, “The Law of the Sea,” parts 1 and 2, The New Yorker, 1 08 1983, pp. 38–65, and 8 August 1983, pp. 56–83, respectivelyGoogle Scholar.

²² As early as 1975, the UNEP funded a World Meteorological Organization (WMO) technical conference on implications of U.S. ozone layer research. But the immediate precursor of the negotiating conference in Vienna came in March 1977, when the UNEP sponsored a policy meeting of governments and international agencies in Washington, D.C., that drafted a “World Plan of Action on the Ozone Layer.” See Benedick, , Ozone Diplomacy, p. 40Google Scholar.

²³ The Intergovernmental Panel of Climate Change was set up by the UNEP and WMO after the passage of UN General Assembly Resolution 43/53, A/RES/43/53, 27 January 1989, “Resolution on the Protection of the Global Climate.”

²⁴ Strange, Susan, “Cave! Hie Dragones: A Critique of Regime Analysis,” in Krasner, Stephen D., ed., International Regimes (Ithaca, N.Y.: Cornell University Press, 1983), pp. 337–54Google Scholar; the quotation is on p. 353.

²⁵ Systems in which compliance can only be achieved through extensive use of coercion are rightly regarded as authoritarian and unjust. See Barkun, Michael, Law Without Sanctions: Order in Primitive Societies and the World Community (New Haven, Conn.: Yale University Press, 1968), p. 62Google Scholar.

²⁶ Articles of Agreement of the IMF, 27 December 1945, as amended, Article 8, sec. 5, in United Nations Treaty Series (UNTS), vol. 2, Treaty no. 20 (New York: United Nations, 1947), p. 39Google Scholar. For the conditionality decision, see decision no. 102-(52/l 1) 13 February 1952, “Selected Decisions of the Executive Directors and Selected Documents,” p. 16.

²⁷ Convention on International Civil Aviation, 7 December 1944, Article 90, in UNTS, vol. 15, Treaty no. 102, 1948, p. 295Google Scholar.

²⁸ Montreal Protocol on Substances that Deplete the Ozone Layer, in International Legal Materials, vol. 26, 1987, p. 1541Google Scholar, Article 2(9) (signed 16 September 1987 and entered into force 1 January 1989; hereafter cited as Montreal Protocol) as amended, London Adjustment and Amendments to the Montreal Protocol on Substances that Deplete the Ozone Layer, in International Legal Materials, vol. 30, 1991, p. 537Google Scholar (signed 29 June 1990 and entered into force 7 March 1991; hereafter cited as London Amendments).

²⁹ The Vienna Convention on the Law of Treaties, signed 23 May 1969 (entered into force on 27 January 1980), Article 2(l)(a), states that“‘treaty’ means an international agreement concluded between States in written form and governed by international law, whether embodied in a single instrument or in two or more related instruments and whatever its particular designation.” See UN Doc. A/CONF. 39/27.

³⁰ According to Young, “‘obligation’ encompasses incentives to comply with behavioral prescriptions which stem from a general sense of duty and which do not rest on explicit calculations of costs and benefits.… Feelings of obligation often play a significant role in compliance choices.” Moreover, “rules constitute an essential feature of bureaucracies and… routinized compliance with rules is a deeply ingrained norm among bureaucrats.” See Young, , Compliance and Public Authority, pp. 23 and 39Google Scholar. See also Fallon, R. H., “Reflections on Dworkin and the Two Faces of Law,” Notre Dame Law Review, vol. 67, no. 3, 1992, pp. 553–85Google Scholar, summarizing H. L. A. Hart's concept of a law as a social rule: “From an internal point of view-that of an unalienated participant of the social life of the community-a social rule is a standard that is accepted as a guide to conduct and a basis for criticism, including self-criticism” (p. 556); Rheinstein, , Max Weber on Law in Economy and Society, pp. 349–56Google Scholar; and Kratochwil, Friedrich V., Rules, Norms, and Decisions: On the Conditions of Practical and Legal Reasoning in International Relations and Domestic Affairs (Cambridge: Cambridge University Press, 1989), pp. 15 and 95–129CrossRefGoogle Scholar.

³¹ We use “norm” as a generic term including principles, precepts, standards, rules, and the like. For present purposes, it is adequate to think of legal norms as norms generated by processes recognized as authoritative by a legal system. Compare Hart, H. L. A., The Concept of Law (Oxford: Oxford University Press, 1961)Google Scholar.

³² The Vienna Convention on the Law of Treaties, Article 26, specifies that “every treaty in force is binding upon the parties to it and must be performed in good faith.” See also chap. 30 of McNair, Arnold Duncan, The Law of Treaties (Oxford: Clarendon Press, 1961), pp. 493–505Google Scholar.

³³ Eskridge, William Jr,. and Peller, G., “The New Public Law: Moderation as a Postmodern Cultural Form,” Michigan Law Review 89 (02 1991), pp. 707–91CrossRefGoogle Scholar.

³⁴ See Ostrom, Elinor, Governing the Commons: The Evolution of Institutions for Collective Action (Cambridge: Cambridge University Press, 1990)CrossRefGoogle Scholar; and Ellickson, Robert C., Order Without Law: How Neighbors Settle Disputes (Cambridge, Mass.: Harvard University Press, 1991)Google Scholar.

³⁵ See Schauer, Frederick F., Playing by the Rules: A Philosophical Examination of Rule-based Decision-making in Law and Life (Oxford: Clarendon Press, 1991)Google Scholar; Kratochwil, , Rules, Norms and Decisions; and Sally Falk Moore, Law as Process (London: Routledge & Kegan Paul, 1978)Google Scholar.

³⁶ Elster, Jon, The Cement of Society: A Study of Social Order (Cambridge: Cambridge University Press, 1989), p. 15CrossRefGoogle Scholar. See also Levi, Margaret, Cook, Karen S., O'Brien, Jodi A., and Fay, Howard, “Introduction: The Limits of Rationality,” in Cook, and Levi, , The Limits of Rationality, pp. 1–16Google Scholar.

³⁷ The quotation is from German Chancellor Theobald von Bethman-Hollweg's remark to the British ambassador about the treaty guaranteeing Belgian neutrality when Germany invaded in 1914. See Encyclopedia Britannica, 14th ed., s.v. Bethman-Hollweg, Theobald von. For an example of the U.S. response, see the letter of ex-President Theodore Roosevelt to British Foreign Secretary Sir Edward Grey dated 22 January 1915, quoted in Morgenthau, Hans J., Politics Among Nations: The Struggle for Power and Peace, 4th ed. (New York: Knopf, 1967)Google Scholar.

³⁸ See, for example, the testimony of General David C. Jones, chairman of the Joint Chiefs of Staff, before the U.S. Senate Committee on Foreign Relations on the Strategic Arms Limitation Talks (SALT) II treaty, Congressional Information Service, S381–24 79, 9 July 1979.

³⁹ It is not clear, however, that democracies are more law-abiding. See Diggs v. Shultz, 470 F. 2d 461 (D.C. Cir. 1972): “Under our constitutional scheme, Congress can denounce treaties if it sees fit to do so, and there is nothing the other branches of the government can do about it. We consider that is precisely what Congress has done in this case” (pp. 466–67).

⁴⁰ International law recognizes a limited scope for abrogation of an agreement in such a case. See the Vienna Convention on the Law of Treaties, Article 62. Generally, however, the possibility of change is accommodated by provisions for amendment, authoritative interpretation, or even withdrawal from the agreement. See, for example, the withdrawal provision of the ABM Treaty, Article 25(2), or the Limited Test Ban Treaty, Article 4. None of these actions poses an issue of violation of legal obligations, though they may weaken the regime of which the treaty is a part.

⁴¹ Keohane surveyed two hundred years of U.S. foreign relations history and identified only forty “theoretically interesting” cases of “inconvenient” commitments in which there was a serious issue of whether or not to comply. See the chapter entitled “Commitments and Compromise,” in Keohane, Robert O., “The Impact of Commitments on American Foreign Policy,” manuscript, 1993, pp. 1–49Google Scholar.

⁴² See Vienna Convention on the Law of Treaties, Article 26; Oppenheim, Lassa, International Law: A Treatise, 8th ed., ed. Lauterpacht, H. (London: Longmans, 1955), p. 956Google Scholar; and McNair, , The Law of Treaties, p. 465Google Scholar.

⁴³ See Chayes, Abram and Chayes, Antonia Handler, “Living Under a Treaty Regime: Compliance, Interpretation, and Adaptation,” in Chayes, Antonia Handler and Doty, Paul, eds., Defending Deterrence: Managing the ABM Treaty Regime into the 21st Century (Washington, D.C.: Pergamon-Brassey's International Defense Publishers, 1989), chap. 11Google Scholar. See also Young, , Compliance and Public Authority, pp. 106–8Google Scholar, which discusses issues of interpretation in the context of deliberate attempts at “evasion” of obligation. We argue that alternative interpretations are frequently invoked in good faith. No doubt in practice there is often some of both.

⁴⁴ See Kennedy, Duncan, “Form and Substance in Private Law Adjudication,” Harvard Law Review 89 (06 1976), pp. 1685–788CrossRefGoogle Scholar; Dworkin, Ronald, “The Model of Rules,” University of Chicago Law Review 35 (Autumn 1967), pp. 14–16CrossRefGoogle Scholar; Kaplow, Louis, Rules Versus Standards: An Economic Analysis, Discussion Paper no. 108Google Scholar, Program in Law and Economics, Harvard, Law School, 04 1992Google Scholar.

⁴⁵ North Atlantic Treaty, Article 3, 63 stat. 2241 (signed 4 April 1949 and entered into force 24 August 1949), in UNTS, vol. 34, no. 541, 1949, p. 243Google Scholar.

⁴⁶ Chayes, Abram and Chayes, Antonia Handler, “Compliance Without Enforcement: State Behavior Under Regulatory Treaties,” Negotiation Journal 7 (07 1991), pp. 311–31CrossRefGoogle Scholar. See also Sohn, Louis B., “Peaceful Settlement of Disputes in Ocean Conflicts: Does UN Clause 3 Point the Way?” Law and Contemporary Problems 46 (Spring 1983), pp. 195–200CrossRefGoogle Scholar. Our work-in-progress examines signs of a recent trend toward more formal dispute resolution procedures in such areas as trade, the law of the sea, and others. The current emphasis in the United States on alternative dispute resolution suggests that international judicial settlement may not be an entirely unmixed blessing, however.

⁴⁷ Schachter, Oscar, “The Invisible College of International Lawyers,” Northwestern University Law Review, vol. 72, no. 2, 1977, pp. 217–26Google Scholar.

⁴⁸ Duffy, Gloria, Compliance and the Future of Arms Control: Report of a Project Sponsored by the Center for International Security and Arms Control (Cambridge, Mass: Ballinger, 1988), pp. 31–60Google Scholar.

⁴⁹ See Chayes, Antonia Handler and Chayes, Abram, “From Law Enforcement to Dispute Settlement: A New Approach to Arms Control Verification and Compliance,” International Security 14 (Spring 1990), pp. 147–64CrossRefGoogle Scholar; and Duffy, , Compliance and the Future of Arms Control, p. 107Google Scholar.

⁵⁰ Superior Oil Co. v. Mississippi, 280 U.S. 390 (1920), p. 395.

⁵¹ Interim Agreement of Limitation of Strategic Arms (SALT I), Article 5(3). See also Compliance with SALT I Agreements, Special Report no. 55, Bureau of Public Affairs, U.S. Department of State, July 1979, p. 4. The issue was finally resolved by Article 15(3) of the SALT II treaty, prohibiting the use over intercontinental ballistic missile silo launchers of shelters that impede verification by national technical means.

⁵² Unilateral assertion is a traditional way of vindicating claimed “rights” in international law. In the spring of 1986, U.S. forces engaged in two such exercises, one off the Soviet Black Sea coast in the “exercise of the right of innocent passage” (The New York Times, 19 03 1986, p. A1Google Scholar) and the other in the airspace over the Gulf of Sidra, which Libya considers its territorial waters and the United States does not. The Black Sea maneuver was concluded with nothing more than some bumping between U.S. and Soviet ships, but in the Gulf of Sidra, U.S. aircraft sank two Libyan patrol vessels that had fired antiaircraft missiles. See Chicago Tribune, 19 March 1986, sec. 1, p. 10; Los Angeles Times, 26 March 1986, p. II; and Los Angeles Times, 27 March 1986, p. II.

⁵³ Consumers Union v. Kissinger, 506 F2d 136 (D.C. Cir. 1974).

⁵⁴ Chayes, and Chayes, , “Living Under a Treaty Regime,” pp. 197 and 200Google Scholar.

⁵⁵ For example, the so-called Foster box rules serve to distinguish between strategic missile reentry vehicles, which are prohibited by the ABM treaty, and tactical missile reentry vehicles, which are not, on the basis of performance characteristics such as velocity and reentry angle not mentioned anywhere in the ABM treaty. See Ashton B. Carter, “Limitations and Allowances for Space Based Weapons,” in Chayes, and Doty, , Defending Deterrence, pp. 132–37Google Scholar.

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⁵⁷ See, for example, Wright, Quincy, “The Cuban Quarantine,” American Journal of International Law 57 (07 1963), pp. 546–65CrossRefGoogle Scholar; Campbell, James S., “The Cuban Crisis and the UN Charter: An Analysis of the United States Position” Stanford Law Review 16 (12 1963), pp. 160–76CrossRefGoogle Scholar; and Standard, William L., “The United States Quarantine of Cuba and the Rule of Law,” American Bar Association Journal 49 (08 1963), pp. 744–48Google Scholar.

⁵⁸ Vienna Convention on the Law of Treaties, Article 2(l)(a).

⁵⁹ Campbell, Kurt M., Carter, Ashton B., Miller, Steven E., and Zraket, Charles A., Soviet Nuclear Fission: Control of the Nuclear Arsenal in a Disintegrating Soviet Union, CSIA Studies in International Security, no. 1, Harvard University, Cambridge, Mass., 11 1991, pp. 24, 25, and 108Google Scholar.

⁶⁰ Hanf, Kenneth, “Domesticating International Commitments: Linking National and International Decision-making,” prepared for a meeting entitled Managing Foreign Policy Issues Under Conditions of Change, Helsinki, 07 1992Google Scholar.

⁶¹ Treaty on the Non-proliferation of Nuclear Weapons, 21 U.S.T. 483 (1970) (signed 1 July 1968 and entered into force 5 March 1970), in International Legal Materials, vol. 7, 1968, p. 809CrossRefGoogle Scholar.

⁶² See Report of the Secretariat on the Reporting of Data by the Parties in Accordance with Article 7 of the Montreal Protocol, UNEP/OzL.Pro.3/5, 23 May 1991, pp. 6–12 and 22–24; and Addendum, UNEP/OzL.Pro3/5/Add.l, 19 June 1991.

⁶³ For the establishment of the Ad Hoc Group of Experts, see Report of the Second Meeting of the Parties to the Montreal Protocol on Substances that Deplete the Ozone Layer, UNEP/OzL.Pro.2/3, Decision 2/9, 29 June 1990, p. 15. At its first meeting in December 1990, the Ad Hoc Group of Experts concluded that countries “lack knowledge and technical expertise necessary to provide or collect” the relevant data and made a detailed series of recommendations for addressing the problem. See Report of the First Meeting of the Ad Hoc Group of Experts on the Reporting of Data, UNEP/OzL.Pro/WG.2/1/4, 7 December 1990.

⁶⁴ The now-classical definition of an international regime appears in Krasner, “Structural Causes and Regime Consequences,” p. 2: “Regimes are sets of implicit or explicit principles, norms, rules, and decision-making procedures around which actors0' expectations converge in a given area of international relations.” Regime theorists find it hard to say the “L-word” but “principles, norms, rules, and decision-making procedures” are what international law is all about, and it is apparent from their work that formal legal norms, most often embodied in treaties, are an important structural element in most of the phenomena of interest to them.

⁶⁵ See Articles of Agreement of the International Monetary Fund, Article 14, in UNTS, vol. 2, 1945, p. 1501Google Scholar; and Montreal Protocol, Article 5.

⁶⁶ Under START, the agreed reductions in strategic nuclear weapons are to take place over a seven-year period divided into three phases of three, two, and two years. See U.S. Congress, Senate, Treaty Between the United States and the Union of Soviet Socialist Republics on the Reduction and Limitation of Strategic Offensive Arms, 102d Cong., 1st sess., 1991, S. Treaty Doc. 102–20, Article 2.

⁶⁷ Vienna Convention for the Protection of the Ozone Layer (signed 22 March 1985 and entered into force 22 September 1988; hereafter cited as Vienna Ozone Convention), Article 2(2), in International Legal Materials, vol. 26, 1986, p. 1529Google Scholar.

⁶⁸ Montreal Protocol, Article 2(4).

⁶⁹ London Amendments, Annex 1, Articles 2A(5) and 2B(3).

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⁷³ Constitution of the International Labor Organization, 11 April 1919, Article 405, 49 stat. 2722.

⁷⁴ Conference on Security and Cooperation in Europe, Final Act (1 August 1975), Article 10, in International Legal Materials, vol. 14, 1975, p. 1292CrossRefGoogle Scholar.

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⁷⁸ See Sanger, David, “North Korea Assembly Backs Atom Pact,” The New York Times, 10 04 1992, p. A3Google Scholar; and Sanger, David, “North Korea Reveals Nuclear Sites to Atomic Agency,” The New York Times, 1 05 1992, p. A4Google Scholar. The initial U.S. response included behind-the-scenes diplomatic pressure and encouraging supportive statements by concerned states at IAEA meetings. See Spector, L., Nuclear Ambitions: The Spread of Nuclear Weapons, 1989–1990 (Boulder, Colo.: Westview Press, 1990), pp. 127–30Google Scholar. Japan apparently has refused to consider economic assistance or investment in North Korea until the nuclear issue is cleared up.

⁷⁹ Countries that have not ratified the NPT include Argentina, Brazil, China, France, India, Israel, and Pakistan. See Spector, Nuclear Ambitions, p. 430.

⁸⁰ Reuters News Service, “Argentina and Brazil Sign Nuclear Accord,” The New York Times, 14 12 1991, p. 7Google Scholar; “Brazil and Argentina: IAEA Safeguard Accord,” U.S. Department of State Dispatch, 23 12 1991, p. 907Google Scholar; Reuters News Service, “South Africa Signs a Treaty Allowing Nuclear Inspection”, The New York Times, 9 07 1991, p. A11Google Scholar; and “Fact Sheet: Nuclear Non-proliferation Treaty,” U.S. Department of State Dispatch, 8 07 1991, p. 491Google Scholar.

⁸¹ The 1977 Congress enacted a requirement for “adequate verification” of arms control agreements. This was described by Carter administration officials as a “practical standard” under which the United States would be able to identify significant attempted evasions in time to respond effectively. See Chayes, and Chayes, , “From Law Enforcement to Dispute Settlement,” pp. 147–48Google Scholar. It should be noted that when the Soviet Union in 1987 finally agreed to substantially unlimited on-site inspection, the United States drew back from its earlier insistence on that requirement, as it has in chemical warfare negotiations.

⁸² Withdrawal from all U.S.-Soviet arms control agreements is permitted on short notice if “extraordinary events related to the subject matter of the treaty jeopardize the supreme interests” of the withdrawing party. See, for example, Treaty Between the United States and the Soviet Union on the Limitation of Antiballistic Missile Systems, 26 May 1972, Article 15(2), 23 U.S.T. 3435 (1972). The law of treaties also permits the suspension of a treaty in whole or in part if the other party has committed a material breach. See the Vienna Convention on the Law of Treaties, Article 60(1) (2).

⁸³ The closest approach to such an initiative was the mildly comic bureaucratic squabble in the closing years of the Reagan administration about whether the Krasnoyarsk radar should be denominated a material breach of the ABM treaty. See Lewis, Paul, “Soviets Warn U.S. Against Abandoning ABM Pact,” The New York Times, 2 09 1988, p. A9Google Scholar; and Gordon, Michael R., “Minor Violations of Arms Pact Seen,” The New York Times, 3 12 1988, p. 5Google Scholar.

⁸⁴ U.S. General Accounting Office, International Environment: International Agreements Are Not Well-Monitored, GAO, RCED-92–43, spring 1992Google Scholar.

⁸⁵ See Report of the Secretariat on the Reporting of Data by the Parties in Accordance with Article 7 of the Montreal Protocol, UNEP/OzL.Pro.3/5, 23 May 1991, pp. 6–12 and 22–24; and Addendum, UNEP/OzL.Pro.3/5/Add.l, 19 June 1991.

⁸⁶ For a report of Japan's announcement of its intention not to enter a reservation on the last day of the conference, see United Press International, “Tokyo Agrees to Join Ivory Import Ban,” Boston Globe, 21 10 1989, p. 6Google Scholar. Japan stated that it was “respecting the overwhelming sentiment of the international community.” As to Hong Kong, see Perlez, Jane, “Ivory Ban Said to Force Factories Shut,” The New York Times, 22 05 1990, p. A14Google Scholar. The Hong Kong reservation was not renewed after the initial six-month period. Five African producer states with effective management programs did enter reservations but agreed not to engage in trade until at least the next conference of the parties. See Glennon, Michael J., “Has International Law Failed the Elephant,” American Journal of International Law 84 (01 1990), pp. 1–43CrossRefGoogle Scholar, especially p. 17. At the 1992 meeting they ended their opposition. See “Five African Nations Abandon Effort to Resume Elephant Trade in CITES Talks,” Bureau of National Affairs Environment Daily, electronic news service, 12 03 1992Google Scholar.

⁸⁷ United Press International, “Tokyo Agrees to Join Ivory Import Ban,” Boston Globe, 21 10 1989Google Scholar.

⁸⁸ Olson, Mancur, The Logic of Collective Action (Cambridge, Mass.: Harvard University Press, 1971), pp. 33–36Google Scholar.

⁸⁹ For a discussion of critical-mass behavior models, see Schelling, Thomas, Micromotives and Macro behavior (New York: Norton, 1978), pp. 91–110Google Scholar.

⁹⁰ See Becker, Gary, “Crime and Punishment: An Economic Approach,” Journal of Political Economy 76 (03/04 1968), pp. 169–217CrossRefGoogle Scholar; and Stigler, , “The Optimum Enforcement of Laws,” p. 526Google Scholar. Also see Young, , Compliance and Public Authority, pp. 7–8 and 111–27Google Scholar.

⁹¹ Lindblom, Charles E., Politics and Markets (New York: Basic Books, 1977), pp. 254–55Google Scholar. At the domestic level, the decision whether to intensify enforcement of the treaty implicates a similar political process, as the continuous debates in the United States over GATT enforcement testify. Our work-in-progress includes a consideration of second-level enforcement.

⁹² Mitchell, Ronald, “Intentional Oil Pollution of the Oceans: Crises, Public Pressure, and Equipment Standards,” in Haas, Peter M., Keohane, Robert O., and Levy, Mark A., eds., Institutions for the Earth: Sources of Effective International Environmental Protection (Cambridge, Mass.: MIT Press, forthcoming)Google Scholar.

⁹³ United States Code, Title 19, Section 2411. Section 301, however, has been widely criticized as itself a violation of GATT. See Sykes, A. O., “Constructive Unilateral Threats in International Commercial Relations: The Limited Case for Section 301,” Law and Policy in International Business 23(Spring 1992), pp. 263–330Google Scholar; and Bayard, Thomas O. and Elliott, Kimberly A., “Aggressive Unilateralism and Section 301: Market Opening or Market Closing,” The World Economy 15 (11 1992), pp. 685–706Google Scholar.

⁹⁴ GATT, Articles 22 and 23, 30 October 1947, as amended. See “GATT Basic Instruments and Selected Documents,” in UNTS, vol. 55, no. 814, 1950, p. 194Google Scholar.

⁹⁵ See Andresen, Steinar, “Science and Politics in the International Management of Whales,” Marine Policy, vol. 13, no. 2, 1989, p. 99CrossRefGoogle Scholar; and Birnie, Patricia, International Regulation of Whaling (New York: Oceana, 1985)Google Scholar.

⁹⁶ See Peter M. Haas, “Protecting the Baltic and North Seas,” in Haas, Keohane, and Levy, Institutions for the Earth.

⁹⁷ For an account of the Iraqi response, see Sean Cote, A Narrative of the Implementation of Section C of UN Security Council Resolution 687.