The Comprehensive Nuclear Test-Ban Treaty ("The Treaty" or "CTBT") consists of the Articles of the Treaty and the following documents:

    Annex 1 to the Treaty - List of States Pursuant to Article II, Paragraph 28;

    Annex 2 to the Treaty - List of States Pursuant to Article XIV;

    Protocol to the Comprehensive Nuclear Test-Ban Treaty;

    Annex 1 to the Protocol (lists of monitoring stations); and

    Annex 2 to the Protocol - List of Characterisation Parameters for International Data Centre Standard Event Screening.

Each of these documents is an integral part of the Treaty, and therefore has the same legally binding status as the Articles.


The Preamble to the Treaty provides an insight into the object and purpose of the Treaty and States Parties' views and expectations in entering into the Treaty.

The first paragraph records the States Parties' appreciation of recent achievements in the field of nuclear arms control and nonproliferation. These achievements have included bilateral agreements between the United States and the former Soviet Union, e.g., the INF and START I and II agreements, and multilateral achievements such as the indefinite extension of the Nuclear Non-Proliferation Treaty (the NPT) with its attendant document "Principles and Objectives for Non-Proliferation and Disarmament."

Paragraph two of the Preamble reflects the States Parties' underscoring of the importance of full implementation of the agreements and measures referred to in the first paragraph.

Paragraph three reflects the States Parties' conviction that the "present international situation" is conducive to further measures toward nuclear disarmament and nonproliferation efforts. The reference to the present situation is a reference primarily to the easing of East-West tensions associated with the end of the Cold War. In this context, the paragraph also states a declaration of intent on the part of the States Parties to take further effective measures towards nuclear disarmament and against the proliferation of nuclear weapons in all its aspects. As indicated in preambular paragraph 5, the Treaty is viewed as an effective measure against proliferation "in all its aspects" because the cessation of all nuclear explosions will have the effect of constraining not only nuclear weapons development by nonnuclear-weapon states ("horizontal" proliferation), but also the effect of constraining the qualitative improvement of nuclear weapons and of ending the development of advanced new types of nuclear weapons by the nuclear-weapon states ("vertical" proliferation). This language does not imply that the Treaty prohibits the development of new types of nuclear weapons, or the improvement of existing weapons; it does recognize that the Treaty will have the effect of constraining such activities.

Paragraph four is a restatement of the need for progress toward reducing nuclear weapons, and a reiteration of the ultimate goal of eliminating nuclear weapons and achieving "general and complete disarmament under strict and effective international control" that appears or is referenced, in almost identical form, in most of the arms control agreements negotiated over the past thirty years that deal in any way with nuclear weapons, e.g., the NPT, the Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Underwater (the LTBT), the Threshold Test-Ban Treaty and the Anti-Ballistic Missile Treaty.

Paragraph five notes the States Parties' recognition that the cessation of all nuclear explosions will constitute an effective measure of disarmament and nonproliferation in all its aspects. The paragraph states that the cessation of nuclear explosions will constrain development and qualitative improvement of nuclear weapons and end the development of advanced new types of nuclear weapons. These effects are recognized as constituting "an effective measure of nuclear disarmament and non-proliferation in all its aspects."

The sixth paragraph sets forth the States Parties' recognition that because of the effects described in paragraph five (the term "thus" is a reference to the antecedent description of the effects of an end to nuclear explosions), an end to all nuclear explosions will be a meaningful step in the fulfillment of a systematic process toward nuclear disarmament.

Paragraph seven records the States Parties' belief that the most effective way to achieve an end to all nuclear explosive testing is by means of a universal, and internationally and effectively verifiable, comprehensive nuclear test ban treaty, and notes that this has long been a priority item on the international disarmament and nonproliferation agenda.

Paragraph eight notes that the Parties to the 1963 Limited Test-Ban Treaty expressed the hope in that Treaty that all test explosions of nuclear weapons would be banned for all time, i.e., that nuclear explosions in the single remaining environment in which they were not banned by the 1963 Treaty, underground, would eventually be banned.

Paragraph nine notes that the Treaty could contribute to the protection of the environment.

Finally, paragraph ten affirms the purpose of attracting the adherence of all states to the Treaty and its objective to contribute effectively (through the "cessation of all nuclear weapon test explosions and all other nuclear explosions") to the prevention of proliferation of nuclear weapons in all its aspects, to the process of disarmament, and therefore to the enhancement of international peace and security. Paragraph 10 emphasizes that the CTBT's ban on all nuclear explosions has the effect of contributing to the prevention of the proliferation of nuclear weapons and to the process of nuclear disarmament.