High contracting parties

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 contracting parties and their joint objectives in executing the treaty, as well as summarizing any underlying events (such as a war). 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 contracting parties' full names or sovereign titles are often included in the preamble, along with the full names and titles of their 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 states) and found them in good or proper form.

The end of the preamble and the start of the actual agreement is often signaled by the words "have agreed as follows."

After the preamble comes numbered articles, which contain the substance of the parties' actual agreement. Each article heading usually encompasses a paragraph. A long treaty may further group articles under chapter headings.

Modern treaties, regardless of subject matter, usually contain articles governing where the final authentic copies of the treaty will be deposited and how any subsequent disputes as to their interpretation will be peacefully resolved.

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