Sui generis is something unique and of its own species or class. In the law, it is a notion of art used to identify a legal classification that exists independently of other categorizations, either because of its singularity or because of the specific creation of a claim or obligation.  For example, the contempt powers of a court are born sui generis and are not the status or rule.  The New York Court of Appeals used this term to describe co-operative housing companies, primarily because this form of housing is considered real estate for certain purposes and as property for other purposes.  In political philosophy, the unprecedented development of the European Union in relation to other international organizations has led to its designation as a geopolitical entity of sui generis. The legal nature of the EU is the subject of a wide debate, as its mixture of intergovernmental and supranational elements allows it to share characteristics with Confederate and federated entities. It is generally regarded as more than one confederation, but less as a federation, is therefore considered an example of either political form. Compared to other international organisations, the EU is often regarded as a “sui generis” because its legal system is totally opposed to any application of retaliatory sanctions by one Member State against another.  The slogan “Sui Generis” was taken up by the Akitsiraq Law School because it is a sui generis (aboriginal) title in all Aboriginal legal institutes in Canada, entitled Inuktitut, the Aboriginal language of Inuit in Canada`s Far North. More importantly, in the professional legal education of Aboriginal people, the work of Aboriginal people to define and create contemporary Aboriginal education is a thing of their artistatic, which has sui generis and sui generis curriculum amenities.  In THE United Kingdom`s planning legislation, including the 1987 Urban Planning and Planning Regulation, many types of land use are classified as specific “use classes.” Changing the use of land within a use class does not require a building permit; However, change between usage classes may require planning permission and authorization is still required when the new use is sui generis.
A similar case that led to the use of the sui generis label is the relationship between New Caledonia and France, because the legal status of New Caledonia may lie somewhere between an overseas French community and a sovereign nation. Although there may be other examples of such status for other dependent or controversial areas, this regime is unique within French space. If a case is sui generis, it means that it is so unique that its underlying justification may not be broadly interpreted. The legal status of the Holy See has also been described as a sui generis unit with an international personality. In the case of cases and other authorities, lawyers and judges may refer to a “sui generis case” or “sui generis authority”, i.e. a specific authority that is limited to their own facts and therefore cannot be broadly applied. Typically, the term sui generis is used by the courts to refer to a case, legal concept or doctrine that is unique. The Joint Council of Municipalities in Croatia is a sui generis council of municipalities in the east of the country, which is formed under an international agreement for the protection of the rights of the Ethnic Serb community in the region and is as such unique in Croatia.    In order to cede a case as a stare decisis, a court may find that the proposed case is sui generis and is therefore not applicable according to the principles of the decisis stare.