- intermittent tremor
- International League for Human Rights , ILHR
- International Security Assistance Force . ISAF
- international affair
- international bonds
- international convergence
- International Workingmen's Association , IWA
- International Working Union of Socialist Parties , IWUSP
- International Labour Organization , ILO
- international division of labor
- International Astronomical Union , IAU
- International Atomic Energy Agency , IAEA
- international atomic time scale
- international orientation
- international exposition
- international show
- IBRD : international Bank for Reconstruction and Developement
- international banking facility , IBF
- International Bank Account Number , IBAN
- International Commission on Illumination , CIE
- international vocational education , IVE
- international visitors
- International Nuclear Event Scale , INES
- international relations , IR
- International Date Line , IDL
- international dimension
- international level
- international unit , IU
- International Skating Union , ISU
- International Telecommunication Union , ITU
- International Telecommunication Union, ITU
- International Geographical Union , IGU
- International Society for Human Rights , ISHR
- International Society for Photogrammetry and Remote Sensing , ISPRS
- International Society for Sexual Medicine , ISSM
- International Chamber of Commerce , ICC
- International Cartographic Association , ICA
- international candle power
- International Communists of Germany
- international crisis
- international phonetic alphabet , IPA
- International Lenin Prize for Strengthening Peace Among Peoples