| ISST | International Ski & Sun Team | In English | → Organizations and associations → 786 |
| ISST | International Society for the Study of Time | In English | → Organizations and associations |
| ISST | Institute for Software and Systems = ISST | Institut für Software- und Systemtechnik | In German |
In English | → Software |
| ISST | International Society of Seed Technologists | In English | → Organizations and associations → Agricultural sciences |
| ISST | Institut für Software- und Systemtechnik = (look above) |
In German | → Software |
| ISSTD | International Society for the Study of Trauma and Dissociation | In English | → Organizations and associations → Neurology |
| IssUP | Issledovaniia po Uprugosti i Plastichnosti | In Russian | → Serial publications, periodicals |
| IssZK | Исследование Земли из Космоса = IssZK | Issledovanie Zemli iz Kosmosa | In Russian |
In Russian | → Serial publications, periodicals → Astronomy |
| IssZK | Issledovanie Zemli iz Kosmosa = (look above) |
In Russian | → Serial publications, periodicals → Astronomy |
| IST | Issues in Science and Technology | In English | → Serial publications, periodicals → Mathematics and natural sciences → Engineering, technology |
| IST | Istituto Scientifico Tumori | In Italian | → Research institutes → Oncology |
| IST | Íslenkir Staðlar | In English | → Standardization |
| ISTA | International Seed Testing Association | In English | → Associations → Agricultural sciences |
| ISTAG | Information Society Technologies Advisory Group | In English | → Organizations and associations → Networks, communication → Telecommunications |
| ISTH | International Society on Thrombosis and Haemostasis | In English | → Organizations and associations → Cardiology |
| ISTI | Istituto di Scienza e Tecnologie dell'Informazione | In Italian | → Computer science → Telecommunications |
| ISTK | Internacia Studumo pri Turismo kaj Kulturo | In Esperanto | → Tourism → Specialized or (poly)technical colleges → Civilization, culture, progress |
| ISU | International System of Units | In English | → 006 |
| ISUOG | International Society of Ultrasound in Obstetrics and Gynecology (www.isuog.org) | In English | → Organizations and associations → Diagnostics → Gynaecology, obstetrics |
| ISV | Independent Software Vendor | In English | → Software → Trade |
| IT | Informationstechnik = IT | Information Technology | In English = IT | Inligtingstegnologie | In Afrikaans = TI | Tecnologia da Informação | In Portuguese = TI | Tecnoloxías da información | In Galician |
In German | → Computer science → Telecommunications |
| IT | Inligtingstegnologie = TI (look above) |
In Afrikaans | → Computer science → Telecommunications |
| IT | Information Technology = TI (look above) |
In English | → Computer science → Telecommunications |
| IT | Informatie Technologie | In Frisian | → Computer science → Telecommunications |
| ITAA | Information Technology Association of America | In English | → Associations → Computer science → Telecommunications |
| ITAB | Institut Teoreticheskoi Astronomii, Biulleten | In Russian | → Serial publications, periodicals → Astronomy |
| ITAC | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Automatic Control | In English | → Serial publications, periodicals → Electrical engineering |
| iTACITUS | Intelligent Tourism And Cultural Information Through Ubiquitous Services | In English | → Networks, communication → Civilization, culture, progress → Tourism |
| ITAES | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Aerospace Electronic Systems | In English | → Serial publications, periodicals → Electronics → Spaceflight engineering, astronautics |
| ITAP | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Antennas and Propagation | In English | → Serial publications, periodicals → Telecommunications |
| ITAS | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Applied Superconductivity | In English | → Serial publications, periodicals → Physics → Applied sciences, technology |
| ITASEAS | Italian Association for Southeast Asian Studies | In English | → Associations → Area studies |
| ITASS | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Acoustics, Speech and Signal Processing | In English | → Serial publications, periodicals → Acoustics → Telecommunications → Language, linguistics, literature |
| ITB | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Broadcasting | In English | → Serial publications, periodicals → Telecommunications |
| ITBE | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Biomedical Engineering | In English | → Serial publications, periodicals → Medicine |
| ITCAD | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Computer Aided Design | In English | → Serial publications, periodicals → Computer-based techniques → 62001 |
| ITCHM | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Components Hybrids and Manufacturing Technology | In English | → Serial publications, periodicals → Engineering, technology |
| ITCmp | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Computers | In English | → Serial publications, periodicals → Hardware |
| ITCom | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Communications | In English | → Serial publications, periodicals → Telecommunications |
| ITCS | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Circuits Systems | In English | → Serial publications, periodicals → Electronics |
| ITDEI | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Dielectrics and Electrical Insulation | In English | → Serial publications, periodicals → Electrical engineering |
| ITDS | IBM Tivoli Directory Server | In English | → Software |
| ITEA | Information Technology for European Advancement | In English | → Computer science → Telecommunications |
| ITED | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Electronic Devices | In English | → Serial publications, periodicals → Electronics |
| ITEdu | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Education | In English | → Serial publications, periodicals → Education → Electrical engineering |
| ITEI | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Electrical Insulation | In English | → Serial publications, periodicals → Electrical engineering |
| ITElC | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Electromagnetic Compatibility | In English | → Serial publications, periodicals → Electromagnetism → Electrical engineering |
| ITEM | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Engineering Management | In English | → Serial publications, periodicals → Engineering, technology |
| ITEnC | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Energy Conversion | In English | → Serial publications, periodicals → Energy economics |
| ITeR | Informatietechnologie en Recht | In Dutch | → Computer science → Law, jurisprudence |
| ITGE | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Geoscience Electronics | In English | → Serial publications, periodicals → Earth sciences → Electronics |
| ITGRS | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Geoscience and Remote Sensing | In English | → Serial publications, periodicals → Earth sciences |
| ITI | Instituto Tecnológico de Informática (www.iti.upv.es) | In Spanish | → Research institutes → Computer science |
| ITIA | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Industry Applications | In English | → Serial publications, periodicals → Engineering, technology |
| ITIE | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Industrial Electronics | In English | → Serial publications, periodicals → Electronics |
| ITIEC | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Industrial Electronics and Control Instrumentation | In English | → Serial publications, periodicals → Electronics |
| ITIL | IT Infrastructure Library | In English | → Libraries → Computer science → Telecommunications |
| ITIM | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Instrumentation Measurement | In English | → Serial publications, periodicals → Mathematics and natural sciences |
| ITIP | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Image Processing | In English | → Serial publications, periodicals → Computer science |
| ITIT | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Information Theory | In English | → Serial publications, periodicals → 007 |
| ITM | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Magnetics | In English | → Serial publications, periodicals → Magnetism |
| ITMI | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Medical Imaging | In English | → Serial publications, periodicals → Diagnostics |
| ITMTT | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Microwave Theory Techniques | In English | → Serial publications, periodicals → Electricity, magnetism, electromagnetism |
| ITNN | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Neural Networks | In English | → Serial publications, periodicals → Computer science → 007 |
| ITNS | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Nuclear Science | In English | → Serial publications, periodicals → Nuclear, atomic, and molecular physics → Nuclear technology |
| ITO | International Trade Organization | In English | → Organizations and associations → Trade → International economic cooperation |
| ITPAM | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Pattern Analysis and Machine Intelligence | In English | → Serial publications, periodicals → Computer science → Mathematics |
| ITPAS | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Power Apparatus Systems | In English | → Serial publications, periodicals → Electrical engineering |
| ITPD | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Power Delivery | In English | → Serial publications, periodicals → Electrical engineering |
| ITPE | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Power Electronics | In English | → Serial publications, periodicals → Electronics |
| ITPHP | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Parts Hybrids and Packaging | In English | → Serial publications, periodicals |
| ITPS | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Plasma Science | In English | → Serial publications, periodicals → Plasma physics |
| ITQB | Instituto de Tecnologia Química e Biológica | In Portuguese | → Research institutes → Biological sciences → Chemical technology |
| ITR | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Reliability | In English | → Serial publications, periodicals → Engineering, technology |
| ITRA | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Robotics Automation | In English | → Serial publications, periodicals → Engineering, technology |
| ITRE | Internacia Traduk-Reto per Esperanto | In Esperanto | → Organizations and associations → Artificial languages (linguistics) |
| ITS | International Tracing Service (http://its-arolsen.org) | In English | → Organizations and associations |
| ITS | Intercept Trajectory Simulation | In English | → Computer simulation → Vehicle engineering |
| ITS | Institut de Traitement des Signaux | In French | → Computer-based techniques → Telecommunications |
| ITS | Issue and Tracking System | In English | → Management |
| ITSC | Interregional Telecommunications Standards Committee | In English | → Organizations and associations → Networks, communication → Telecommunications |
| ITSE | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Software Engineering | In English | → Serial publications, periodicals → Software |
| ITSF | Integral Transforms and Special Functions | In English | → Serial publications, periodicals → Integral calculus |
| ITSM | IT Service Management | In English | → Computer science |
| ITSMC | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Systems, Man and Cybernetics | In English | → Serial publications, periodicals → Computer science |
| ITSP | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Signal Processing | In English | → Serial publications, periodicals → Telecommunications |
| ITSTC | Information Technology Steering Committee | In English | → Organizations and associations → Computer science → Telecommunications |
| ITSTQ | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Selected Topics in Quantum Electronics | In English | → Serial publications, periodicals → Electronics |
| ITSU | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Sonics Ultrasonics | In English | → Serial publications, periodicals → Acoustics |
| ITT | Information Technology and Tourism | In English | → Serial publications, periodicals → Tourism |
| ITTF | Information Technology Task Force | In English | → Computer science |
| ITTO | International Tropical Timber Organization (www.itto.or.jp) = OIBT | Organisation Internationale des Bois Tropicaux | In French = OIMT | Organización Internacional de las Maderas Tropicales | In Spanish |
In English | → Organizations and associations → Nature and society → Timber and woodworking industry |
| ITU | International Telecommunication Union = IUT | Internacia Unio pri Telekomunikado | In Esperanto = UIT | Union Internationale des Télécommunications | In French |
In English | → Organizations and associations → Telecommunications |
| ITU | Institut für Transurane | In German | → Research institutes → Nuclear, atomic, and molecular physics → Nuclear technology |
| ITU-T | International Telecommunications Union - Telecommunications Standardization Sector | In English | → Standardization → Telecommunications |
| ITUC | Interregional Trade Union Council | In English | → Organizations and associations → Labour, labour economics |
| ITUFF | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Ultrasonics, Ferroelectrics and Frequency Control | In English | → Serial publications, periodicals → Acoustics → Electricity, magnetism, electromagnetism → Telecommunications |
| ITUH | International Trade Union House | In English | → Organizations and associations → Labour, labour economics |
| ITVT | IEEE (Institute of Electrical and Electronics Engineers) Transactions on Vehicular Technology | In English | → Serial publications, periodicals → Vehicle engineering |
| IU | Interface Unit | In English | → Human-computer interaction |
| IUA | Interface Unit Adapter | In English | → Human-computer interaction |
| IUCr | International Union of Crystallography (www.iucr.org) | In English | → Organizations and associations → Crystallography |
| IUE | Interface Unit Error | In English | → Human-computer interaction |
| IUEEN | IUE ESA Newsletter | In English | → Serial publications, periodicals → Astronomy |
| IUENN | IUE NASA Newsletter | In English | → Serial publications, periodicals → Astronomy |
| IUI | Integrated User Interface | In English | → Human-computer interaction |
| IULO | International Union of Local Authorities | In English | → Organizations and associations → Municipal administration |
| IUMJ | Indiana University Mathematics Journal | In English | → Serial publications, periodicals → Mathematics |
| IUOTO | International Union of Official Travel Organisations | In English | → Organizations and associations → Tourism |
| IUOTPO | International Union of Official Tourist Publicity Organizations | In English | → Organizations and associations → Tourism |
| IUP | International Usability Partners | In English | → Human-computer interaction |
| IUPAC | International Union of Pure and Applied Chemistry | In English | → Organizations and associations → Chemistry → Chemical technology |
| IUPAK | Internacia Unio pri Pura kaj Aplika Kemio |
In Esperanto | → Organizations and associations → Chemistry → Chemical technology |
| IUPRAI | Indian Unit for Pattern Recognition and Artificial Intelligence | In English | → Organizations and associations → Artificial intelligence → Computer-based techniques |
| IUT | Internacia Unio pri Telekomunikado = ITU, UIT (look above) |
In Esperanto | → Organizations and associations → Telecommunications |
| IV | Industriellenvereinigung (www.iv-net.at) | In German | → Organizations and associations → Industry, industrial policy |
| IVA | Indian Vexillological Association | In English | → Associations → 9299 |
| IVE | Interface Verification Equipment | In English | → Human-computer interaction |
| IVG | Internationale Vereinigung für Germanistik | In German | → Organizations and associations → Language, linguistics, literature |
| İvHP | İnternet ve Hukuk Platformu | In Turkish | → Networks, communication |
| IVK | Institut für Verbrennungskraftmaschinen und Kraftfahrzeugbau (www.ivk.tuwien.ac.at) | In German | → Research institutes → Mechanical engineering → Vehicle engineering |
| IVO | Inspanning Voor Ontspanning | In Dutch | → Organizations and associations → Sport, physical exercises |
| IVP | Interface Verification Plan | In English | → Human-computer interaction |
| IVR | Interactive Voice Recognition | In English | → Computer-based techniques → Telecommunications |
| IVS | In Vriendschap Sterk | In Dutch | → Organizations and associations → Sport, physical exercises |
| IVS | Institut des Vaisseaux et du Sang (www.ivs-vbi.org) = VBI | Vessels and Blood Institute | In English |
In French | → Research institutes → Blood and circulatory system |
| IVS | Interface Verification Summary | In English | → Human-computer interaction |
| IVT | Interface Verification Test | In English | → Human-computer interaction |
| IVV | Ilper Voetbal Vereniging | In Dutch | → Organizations and associations → Sport, physical exercises |
| IWA | International Water Association | In English | → Associations → Hydrology → Environmental technology, water supply, waste management |
| IWC | International Whaling Commission | In English | → Organizations and associations → International relations → Fishing, hunting |
| IWCE | International Workshop on Computational Electronics | In English | → Computer science → Electronics |
| IWEPNM | International Winterschool on Electronic Properties of Novel Materials | In English | → Congresses → Physics → Chemistry |
| IWF | Institut für Weltraumforschung (www.iwf.oeaw.ac.at) | In German | → Research institutes → Astronomy → Spaceflight engineering, astronautics |
| IWF | International Weightlifting Federation (www.iwf.net) | In English | → Organizations and associations → Sport, physical exercises |
| IWFHR | International Workshop on Frontiers in Handwriting Recognition | In English | → Congresses → Writing systems → Document processing |
| IWG | Interface Working Group | In English | → Human-computer interaction |
| IWI | Industriewissenschaftliches Institut | In German | → Research institutes → Industry, industrial policy → Engineering, technology |
| IWM | Institut für die Wissenschaften vom Menschen (www.iwm.at) | In German | → Research institutes → Social sciences |
| IWRS | International Wheelchair Rugby Federation | In English | → Organizations and associations → Football and rugby |
| IWTO | International Wool Textile Organization | In English | → Organizations and associations → Textile industry |
| IYS | Igud Yotzei Sin | In Chinese | → Organizations and associations → Judaism |
| IZA | Innsbrucker Zeitungsarchiv | In German | → Newspapers, journalism |
| IzDus | Dushanbe, Izdatel'stvo Donish | In Russian | → Serial publications, periodicals, |
| IzFru | Frunze, Izdatel'stvo Ilim | In Russian | → Serial publications, periodicals → Mathematics and natural sciences |
| IZT | Institut für Zukunftsstudien und Technologiebewertung (www.izt.de) | In German | → Research institutes → Research policy → Engineering, technology |
| J2EE | Java 2 Enterprise Edition | In English | → Programming languages |
| J2ME | Java 2 Micro Edition | In French | → Programming languages |
| JA | Juna Alumeto | In Esperanto | → Newspapers, journalism |
| JA | Journal Asiatique | In French | → Serial publications, periodicals → Language, linguistics, literature → Geography, biography, history |
| JAAC | Journal of Aesthetics and Art Criticism | In English | → Serial publications, periodicals |
| JAAS | Journal of Asian American Studies | In English | → Serial publications, periodicals → Area studies |
| JAAS | Journal of Assyrian Academic Studies | In English | → Serial publications, periodicals → Language, linguistics, literature → Geography, biography, history |
| JAAS | Java Authentication and Authorization Service | In English | → Programming languages |
| JAAS | Journal of Asian and African Studies | In English | → Serial publications, periodicals → Language, linguistics, literature → Geography, biography, history |
| JAAS | Journal of Analytical Atomic Spectrometry | In English | → Serial publications, periodicals → Nuclear, atomic, and molecular physics → Chromatography, mass spectrography |
| JAAVSO | Journal of the American Association of Variable Star Observers | In English | → Serial publications, periodicals → Astronomy |
| JABS | Justice Awareness and Basic Support | In English | → Organizations and associations → Law, jurisprudence → Pharmacology, toxicology |
| JABS | Just Another Blog on Sports | In English | → Networks, communication → Sport, physical exercises |
| JAC | Journée d'Acquisition des Connaissances | In French | → Knowledge management |
| JAChS | American Chemical Society Journal | In English | → Serial publications, periodicals → Physics |
| JAco | Journal d'Acoustique | In French | → Serial publications, periodicals → Acoustics |
| JACS | Journal of American Ceramic Society | In English | → Serial publications, periodicals → Applied sciences, technology |
| JAD | Journal of Astronomical Data | In English | → Serial publications, periodicals → Astronomy |
| JAE | Journal of Acoustic Emission | In English | → Serial publications, periodicals → Acoustics |
| JAE | Journal of Architectural Education | In English | → Serial publications, periodicals → Education → Architecture |
| JAE | Journal of African Economies | In English | → Serial publications, periodicals → Economics |
| JAEH | Journal of African Economic History | In English | → Serial publications, periodicals → Economics → History |
| JAEL | JSC (Johnson Space Center) Avionics Engineering Laboratory | In English | → Research institutes → Aeronautics, aircraft |
| JAER | Journal of Agricultural Engineering Research | In English | → Serial publications, periodicals → Agricultural sciences |
| JAerE | Journal of Aerospace Engineering | In English | → Serial publications, periodicals → Aeronautics, aircraft → Spaceflight engineering, astronautics |
| JAerP | Journal of Aerospace Power | In English | → Serial publications, periodicals → Electrical engineering → Aeronautics, aircraft → Engineering, technology |
| JAerS | Journal of Aerosol Science | In English | → Serial publications, periodicals → Meteorology, climatology |
| JAES | Journal of Audio Engineering Society | In English | → Serial publications, periodicals → Acoustics |
| JAESc | Journal of Asian Earth Sciences | In English | → Serial publications, periodicals → Earth sciences |
| JAF | Journal des Astronomes Francais | In French | → Serial publications, periodicals → Astronomy |
| JAfES | Journal of African Earth Sciences | In English | → Serial publications, periodicals → Earth sciences |
| JAFS | Japan Asian Association and Asian Friendship Society | In English | → Associations → International relations |
| JAG | Journal of Applied Geophysics | In English | → Serial publications, periodicals → Geophysics |
| JAH | Journal of African History | In English | → Serial publications, periodicals → History |
| JAHH | Journal of Astronomical History and Heritage | In English | → Serial publications, periodicals → Astronomy → History |
| JAICI | Japan Association for International Chemical Information | In English | → Associations → Chemistry |
| JaIMJ | Japan Institute of Metals Journal | In English | → Serial publications, periodicals → Metallurgy |
| JAir | Journal of Aircraft | In English | → Serial publications, periodicals → Aeronautics, aircraft |
| JAIS | Journal of Arabic and Islamic Studies | In English | → Serial publications, periodicals → Islam → Area studies |
| JaJAP | Japanese Journal of Applied Physics | In English | → Serial publications, periodicals → Physics |
| JAL | Journal of Arabic Literature | In English | → Serial publications, periodicals → Literature |
| JAL | Journal of African Languages | In English | → Serial publications, periodicals → Language, linguistics, literature |
| JAL | Journal of African Law | In English | → Serial publications, periodicals → Law, jurisprudence |
| JAlg | Journal of Algebra | In English | → Serial publications, periodicals → Algebra |
| JAlgC | Journal of Algebraic Combinatorics | In English | → Serial publications, periodicals → Algebra → 5191 |
| JAlgo | Journal of Algorithms | In English | → Computer science → Serial publications, periodicals → 5105 |
| JAllC | Journal of Alloys and Compounds | In English | → Serial publications, periodicals → Metallurgy |
| JALPO | Journal of the Association of Lunar & Planetary Observers | In English | → Serial publications, periodicals → Planets and satellites |
| JALT | Japan Association for Language Teaching | In English | → Associations → Education → Linguistics |
| JAM | Junulara Azia Movado | In Esperanto | → Organizations and associations |
| JAMA | Journal of the American Medical Association | In English | → Serial publications, periodicals → Medicine |
| JAMI | Jewish Association for the Mentally Ill | In English | → Associations → 61889 |
| JAMS | Journal of the American Mathematical Society | In English | → Serial publications, periodicals → Mathematics |
| JAMS | Japanese Association for Mathematical Sociology | In English | → Associations → Sociology |