A Declaration and a Recommendation is generally a document of intent, and, in most cases, does not create a legally binding obligation on the countries which have signed it. The terms are often deliberately chosen to indicate that the parties do not intend to create binding obligations but merely want to declare certain aspirations. Declarations and Recommendations cannot be ratified. The term 'declaration' is used for various international instruments. An example is the 1992 Rio Declaration. Declarations can however also be treaties in the generic sense intended to be binding at international law. It is therefore necessary to establish in each individual case whether the parties intended to create binding obligations. Some instruments entitled 'declarations' were not originally intended to have binding force, but their provisions may have reflected customary international law or may have gained binding character as customary law at a later stage. Such was the case with the 1948 Universal Declaration of Human Rights. Declarations that are intended to have binding effects could be classified as follows:
- An interpretative declaration is an instrument that is annexed to a treaty with the goal of interpreting or explaining the provisions of the latter.
- A declaration can also be an informal agreement with respect to a matter of minor importance.
- A series of unilateral declarations can constitute binding agreements. A typical example are declarations under the Optional Clause of the Statute of the International Court of Justice that create legal bonds between the declarants, although not directly addressed to each other.
- A declaration can also be a treaty in the proper sense. A significant example is the Joint Declaration between the United Kingdom and China on the Question of Hong Kong of 1984.