International agreements

A treaty is an agreement under international law entered into by actors in international law, namely sovereign states and international organizations. A treaty may also be known as an (international) agreement, protocol, covenant, convention, pact, or exchange of letters, among other terms. Regardless of terminology, all of these forms of agreements are, under international law, equally considered treaties and the rules are the same.

Treaties can be loosely compared to contracts: both are means of willing parties assuming obligations among themselves, and a party to either that fails to live up to their obligations can be held liable under international law.

A treaty is an official, express written agreement that states use to legally bind themselves. A treaty is the official document which expresses that agreement in words; and it is also the objective outcome of a ceremonial occasion which acknowledges the parties and their defined relationships.

Since the late 19th century, most treaties have followed a fairly consistent format. A treaty typically begins with a preamble describing the High Contracting Parties and their shared objectives in executing the treaty, as well as summarizing any underlying events (such as the aftermath of a war in the case of a peace treaty). Modern preambles are sometimes structured as a single very long sentence formatted into multiple paragraphs for readability, in which each of the paragraphs begins with a gerund (desiring, recognizing, having, and so on).

The High Contracting Parties; referred to as either the official title of the head of state (but not including the personal name), e.g. His Majesty The King of X or His Excellency The President of Y, or alternatively in the form of "Government of Z"; are enumerated, and along with the full names and titles of their plenipotentiary representatives, and a boilerplate clause about how their representatives have communicated (or exchanged) their full powers (i.e., the official documents appointing them to act on behalf of their respective high contracting party) and found them in good or proper form. However, under the Vienna Convention on the Law of Treaties if the representative is the head of state, head of government or minister of foreign affairs, no special document is needed, as holding such high office is sufficient.

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