CNI is the abbreviation for a number of organizations and companies, including:
- Centro Nacional de Inteligencia, the Spanish secret service agency.
- Central Nacional de Informaciones, the (last) Chilean secret service agency during Pinochet's government
- Church of North India
- CityNews International, A Canadian International Newscast which airs on the Citytv stations (excluding Citytv Toronto) and on Toronto's News Station CablePulse24.
- Chickasaw Nation Industries, is a federally chartered corporation wholly owned by the Chickasaw Nation.
- Coalition for Networked Information, an organization of libraries, universities, publishers and telecommunications firms.
- Council for the National Interest, a political advocacy organization based in Washington, D.C.
- Colegio Nacional Iquitos, a Peruvian soccer team.
- Corpo della Nobiltà Italiana, the Italian nobility association.
- Communication Networks Institute, located at Dortmund University of Technology.
- Centre national des indépendants et paysans, a French political party.
- Corporación de Noticias e Información (News and Information Corporation), a news organization in Mexico (see XHTVM-TV)
It is also an abbreviation for:
- Calcineurin inhibitor, a class of immunosuppressive drug.
- Common Network Interface Ring
- Olfactory nerve, or Cranial nerve I
- Compiled Native Interface (previously called Cygnus Native Interface), a Java Native Interface equivalent for the GCJ compiler
- Critical National Infrastructure, the essential systems and services which allow society to continue to function, such as electricity and water supplies.
- Originally Certified NetWare Instructor, then subsequently (when UnixWare entered Novells product range) it became Certified Novell Instructor.
- Certificate of No Impediment: If you are planning on marrying overseas (not in the UK), you may be required to provide the local authorities with a certificate of no impediment (CNI) as evidence that you are single and free to marry.
- Iodine cyanide, which has the alternative chemical formula of CNI.
- Communications, Navigation and Identification (Aerospace).
It is also used as a phonetically similar abbreviation in:
- CNI-dog (or " seeing eye dog"), a guide dog for blind persons.