| IAVCEI | International Association of Volcanology and Chemistry of the Earth's Interior (www.iavcei.org) | In English | → Associations → 55121 → Geochemistry |
| IB | Institut für Bodenforschung (www.boku.ac.at/boden/) | In German | → Research institutes → Agricultural sciences |
| IBA | International Bar Association (www.ibanet.org) | In English | → Associations → Law, jurisprudence |
| IBA | Institute for Biomedical Aging Research | In English | → Research institutes → Biological sciences → Medicine |
| IBAS | Indonesian Business Association of Shanghai | In English | → Associations → Economics |
| IBL | Institut de Biologie de Lille | In French | → Research institutes → Biological sciences |
| IBN | Institute of Bioengineering and Nanotechnology | In English | → Research institutes → Biotechnology |
| IBO | Associazione Italiana Soci Costruttori | In Italian | → Associations |
| ICAANE | International Congress on the Archaeology of the Ancient Near East | In English | → Congresses → Archeology |
| ICAD | International Conference on Alzheimer's Disease (and Related Disorders) | In English | → Congresses → Neurology |
| ICAD | International Conference on Auditory Display | In English | → Congresses → Human-computer interaction → Telecommunications |
| ICAITI | Instituto Centroamericano de Investigación y Tecnología | In Spanish | → Research institutes → Research policy → Engineering, technology |
| ICANAS | International Congress for Asian and Northern African Studies | In English | → Congresses → Area studies |
| ICANN | International Conference on Artificial Neural Networks | In English | → Congresses → Artificial intelligence |
| ICAP | International Conference on Atomic Physics | In English | → Congresses → 53198 |
| ICARDA | International Center for Agricultural Research in the Dry Areas | In English | → Research institutes → Agricultural sciences |
| ICB | International Centre of Biocybernetics | In English | → Research institutes → Computer science → Electronics |
| ICC | International Association for Cereal Science and Technology | In English | → Associations → Agricultural sciences |
| ICCA | International Congress and Convention Association | In English | → Associations → Congresses |
| ICCHP | International Conference on Computers Helping People with Special Needs | In English | → Congresses → Computer-based techniques |
| ICDAR | International Conference on Document Analysis and Recognition | In English | → Congresses → Document processing |
| ICEIS | International Conference on Enterprise Information Systems | In English | → Congresses → Knowledge management → Data |
| ICHSEA | International Conference on the History of Science in East Asia | In English | → Congresses → Mathematics and natural sciences → History |
| ICLP | Institute of Chinese Literature and Philosophy | In English | → Research institutes → Philosophy, psychology → Literature |
| ICMAB | Instituto de Ciencia de Materiales de Barcelona (www.icmab.es) | In Spanish | → Research institutes → Materials science |
| ICMI | International Conference on Multimodal Interfaces | In English | → Congresses → Human-computer interaction |
| ICN | International Conference on Nutrition = CIN | Conferencia Internacional sobre Nutrición | In Spanish = CIN | Conférence Internationale sur la Nutrition | In French = CIN | Conferência Internacional sobre Nutrição | In Portuguese |
In English | → Congresses → Nutrition |
| ICOMTEC | Institut de Communication et des Nouvelles Technologies (http://icomtec.univ-poitiers.fr) | In French | → Higher education, universities → Research institutes → Computer science → Telecommunications |
| ICOPHIL | International Conference on Philippine Studies | In English | → Congresses → Area studies |
| ICPO | Institute of Cytology & Preventive Oncology | In English | → Research institutes → Cytology → Oncology |
| ICPS | International Conference on the Physics of Semiconductors | In English | → Congresses → Electricity, magnetism, electromagnetism → 539 → Electrical engineering |
| ICRA | Association de Classification du Contenu de l'Internet | In French | → Internet → Libraries → Associations |
| ICRAT | International Conference on Research in Air Transportation | In English | → Congresses → Transport and postal services |
| ICS | Institut Clinique de la Souris (www-mci.u-strasbg.fr) | In French | → Research institutes → Medicine → Pharmacology, toxicology |
| ICS | Institut Charles Sadron (www-ics.u-strasbg.fr) | In French | → Research institutes → Physics → Chemistry |
| ICS | Institut de Cinématographie Scientifique (www.ics.cnrs-bellevue.fr) | In French | → Research institutes → Cinema, movies |
| ICS | Ingénierie des Contenus et Savoirs (http://scenari.utc.fr) | In French | → Research institutes → Computer science → Knowledge management |
| ICSA | International Cultic Studies Association | In English | → Associations → Social sciences |
| ICSV | International Congress on Sound and Vibration | In English | → Congresses → Acoustics |
| ICTA | Instituts et Centres Techniques Agricoles | In French | → Research institutes → Agricultural sciences |
| ICTS | International Conference on Thai Studies | In English | → Congresses → Area studies |
| IDA | International Development Association (www.worldbank.org/ida/) = AID | Association Internationale de Développement | In French = AIF | Asociación Internacional de Fomento | In Spanish = AID | Associação Internacional de Desenvolvimento | In Portuguese = МАР | Международная ассоциация развития | In Russian = MAP | Міжнародна асоціація розвитку | In Serbian |
In English | → Associations → Development |
| IDEO | Institut Dominicain d'Études Orientales du Caire | In French | → Research institutes → Roman catholic church → Area studies |
| IDM | Institut für den Donauraum und Mitteleuropa | In German | → Research institutes → International relations → Area studies |
| IDSA | Institute for Defense Studies and Analyses | In English | → Research institutes → Polemology → Military affairs |
| IEAS | Institute of East Asian Studies | In English | → Research institutes → Area studies |
| IEF | International Energy Foundation | In English | → Foundations → Energy economics |
| IEJ | Itala Esperantista Junularo (http://iej.esperanto.it) | In Esperanto | → Associations |
| IEŚW | Instytut Europy Środkowo-Wschodniej | In Polish | → Research institutes |
| IFDA | International Furnishings and Design Association | In English | → Associations → Drawing and applied arts |
| IFEAC | Institut Français d'Études sur l'Asie Centrale | In French | → Research institutes → Area studies |
| IFEAD | Institut Français d'Études Arabes de Damas | In French | → Research institutes → Language, linguistics, literature → Geography, biography, history |
| IFEN | Institut Français de l'Environnement | In French | → Research institutes → Nature → Environment, environmental sciences |
| IFES | Institute of Far Eastern Studies | In English | → Research institutes → Area studies |
| IFK | Internationales Forschungszentrum Kulturwissenschaften (www.ifk.ac.at) | In German | → Research institutes → Civilization, culture, progress |
| IFM | Institut Français de la Mer | In French | → Research institutes → Environment, environmental sciences → Marine research, oceanography |
| IFP | Institut Français du Pétrole | In French | → Research institutes → Earth sciences → Mining → 665 |
| IFR | Institute of Food Research | In English | → Research institutes → Agricultural sciences → Food technology |
| IFRA | INCA-FIEJ Research Association | In English | → Associations → Newspapers, journalism → Graphic industries, printing, publishing |
| IFRI | Institut Français des Relations Internationales | In French | → Research institutes → International relations |
| IFRTP | Institut Français pour la Recherche et la Technologie Polaire | In French | → Research institutes → Earth sciences |
| IFSH | Institut für Friedensforschung und Sicherheitspolitik | In German | → Research institutes → Polemology |
| IFT | Institute of Food Technologists | In English | → Research institutes → Food technology |
| IGDA | International Game Developers Association (www.igda.org) | In English | → Associations → Software → Entertainment |
| IGEER | Instituut voor Geschiedenis van de Europese Expansie | In Dutch | → Research institutes → History |
| IGiPZ | Instytut Geografii i Przestrzennego Zagospodarowania (www.igipz.pan.pl) | In Polish | → Research institutes → Geography |
| IGN | Instituto Geográfico Nacional (www.ign.es) | In Spanish | → Research institutes → Geography |
| IGOR | Institut für Gewebe- und Organrekonstruktion (www.igor.at) | In German | → Research institutes → Biotechnology → Medicine |
| IHP | Institute of History and Philology | In English | → Research institutes → Philology → History |
| IHTP | Institut d'Histoire du Temps Présent (www.ihtp.cnrs.fr) | In French | → Research institutes → History |
| IHV | Institute of Human Virology (www.ihv.org) | In English | → Research institutes → Virology |
| II | Instytut Informatyk | In Polish | → Research institutes → Computer science |
| IIAC | Institut Interdisciplinaire d'Anthropologie du Contemporain | In French | → Research institutes → Sociology |
| IIAT | Institut International d'Agriculture Tropicale = IITA | International Institute of Tropical Agriculture | In English |
In French | → Research institutes → Agricultural sciences |
| IIBHG | Institute of Immunobiology and Human Genetics = IIBHG | Institut za Imunobiologija i Humana Genetika | In Macedonian |
In English | → Research institutes → Genetics → Immunology and allergy |
| IIDA | International Interior Design Association | In English | → Associations → Architecture → Drawing and applied arts |
| IIPA | Irish Interprofessional Association | In English | → Associations |
| IIPA | International Industrial Photographers Association | In English | → Associations → Photography |
| IIPA | Israeli International Pharmacy Association | In English | → Associations → Pharmacology, toxicology |
| IIPA | International Iridology Practitioners Association | In English | → Associations → 6158 |
| IISER | Indian Institute of Science and Education Research (www.iiserpune.ac.in) | In English | → Research institutes → Education |
| IITA | International Institute of Tropical Agriculture = IIAT (look above) |
In English | → Research institutes → Agricultural sciences |
| IJCAI | International Joint Conference on Artificial Intelligence | In English | → Congresses → Artificial intelligence |
| IJK | Internacia Junulara Kongreso | In Esperanto | → Congresses |
| IJM | Institut Jacques Monod (www.ijm.jussieu.fr) | In French | → Research institutes → Biological sciences |
| IJS | Internacia Junulara Semajno | In Esperanto | → Congresses |
| IKSV | İstanbul Kültür Sanat Vakfı | In Turkish | → Foundations |
| ILAC | International Laboratory Accreditation Cooperation | In English | → Research institutes |
| ILCA | (Research) Institute for Languages and Cultures of Asia and Africa | In English | → Research institutes → Civilization, culture, progress → Language, linguistics, literature → Area studies |
| ILM | Institut für Laboratoriumsmedizin, Klinische Chemie und Molekulare Diagnostik | In German | → Research institutes → Biochemistry, biophysics → Pharmacology, toxicology → 6160 |
| IMA | International Medical Association | In English | → Associations → Medicine |
| IMA | Interdisciplinary Medical Association | In English | → Associations → Medicine |
| IMBA | Illinois Mortgage Bankers Association | In English | → Associations → Finance |
| IMBA | International Mountain Bicycling Association (www.imba.com) | In English | → Associations → Sport, physical exercises |
| IMCB | Institute of Molecular and Cell Biology | In English | → Research institutes → Biological sciences |
| IMN | Instytut Metali Nieżelaznych (www.imn.gliwice.pl) | In Polish | → Research institutes → Metallurgy |
| IMP/LMM | Ingénierie des Matériaux Polymères/ Laboratoire Matériaux Macromoléculaires | In French | → Research institutes → Materials science → Plastic industry |
| IMRSA | International Medical Regulatory and Shipping Association | In English | → Associations → Medicine |
| IMS | Institute for Molecular Science | In English | → Research institutes → Biochemistry, biophysics |
| IMSO | International Mobile Satellite Organization | In English | → Associations → Spaceflight engineering, astronautics → Telecommunications |
| INA | International Nanoplankton Association | In English | → Associations → Marine research, oceanography → Palaeontology → Zoology |
| INA | Internacia Naturkuraca Asocio | In Esperanto | → Associations |
| INCA | International Newspaper Colour Association | In English | → Associations → Newspapers, journalism → Graphic industries, printing, publishing |
| INCOPA | Inorganic Coagulants Producers Association (www.incopa.org) | In English | → Associations → Chemicals |
| INED | Institut National d'Études Démographiques | In French | → Research institutes → Demography |
| INERIS | Institut National de l'Environnement Industriel et des Risques | In French | → Research institutes → Nature → Engineering, technology |
| INESASS | Institute of National Economy - Shanghai Academy of Social Sciences | In English | → Research institutes → Economics |
| InESS | Institut d'Électronique du Solide et des Systèmes (www-iness.c-strasbourg.fr) | In French | → Research institutes → Electronics |
| INETI | Instituto Nacional de Engenharia e Tecnologia Industrial | In Portuguese | → Research institutes → Engineering, technology |
| INGV | Istituto Nazionale di Geofisica e Vulcanologia (www.ingv.it) | In Italian | → Research institutes → Geophysics → 55121 |
| INPMA | Institut National des Plantes Médicinales et Aromatiques | In English | → Research institutes → Biological sciences → Pharmacology, toxicology → Agricultural sciences |
| INRETS | Institut National de Recherche sur les Transports et leur Sécurité | In French | → Research institutes → Transport and postal services → Vehicle engineering |
| INRIA | Institut National de Recherche en Informatique et Automatique | In French | → Research institutes → Computer science → Electrical engineering |
| INRIA | Institut National de Recherche en Informatique et en Automatique | In French | → Research institutes → Computer science → Mechanical engineering |
| INRS | Institut National de Recherche et de Sécurité | In French | → Research institutes |
| INSP | Institut des Nanosciences de Paris | In French | → Research institutes → Physics → Chemistry |
| INSTM | Institut National des Sciences et des Techniques Nucléaires | In French | → Research institutes → Nuclear, atomic, and molecular physics → Nuclear technology |
| INTAP | Interoperability Technology Association for Information Processing | In English | → Associations → Telecommunications → Computer-based techniques |
| IOAOB | Instituut voor de Organisatie van de Administraties der Openbare Besturen | In Dutch | → Research institutes → Libraries |
| IOB | Institute of Biology | In English | → Research institutes → Biological sciences |
| IOPAN | Instytut Oceanologii Polskiej Akademii Nauk (www.iopan.gda.pl) | In Polish | → Research institutes → Marine research, oceanography |
| IPA | Independent Practice Association | In English | → Associations → Medicine |
| IPA | International Psychoanalytical Association | In English | → Associations → Psychology |
| IPA | Independent Pilots Association | In English | → Associations → Aeronautics, aircraft |
| IPA | International Publishers' Association | In English | → Associations → Graphic industries, printing, publishing |
| IPA | International Powerlifting Association | In English | → Associations |
| IPA | International Phonetic Association | In English | → Associations → Writing systems |
| IPA | International Police Association | In English | → Associations → Police |
| IPA | Interparlamentarische Arbeitsgemeinschaft | In German | → Associations → Parliaments, representation |
| IPA | Internet Privatstiftung Austria | In German | → Foundations → Networks, communication → Telecommunications |
| IPA | Fraunhofer-Institut für Produktionstechnik und Automatisierung | In German | → Research institutes → Engineering, technology |
| IPC | Institut de Pathologie du Cheval | In French | → Research institutes → Veterinary medicine → Agricultural sciences |
| IPCAA | International Pharmaceutical Congress Advisory Association | In English | → Associations → Congresses → Pharmacology, toxicology |
| IPEA | Internet Positionning European Association | In English | → Associations → Networks, communication → 659 |
| IPFA | International Plasma Fractionation Association | In English | → Associations → Pharmacology, toxicology |
| IPK | Institut für Produktionsanlagen und Konstruktionstechnik (www.ipk.fraunhofer.de) | In German | → Research institutes → Building |
| IPN | Instytut Pamięci Narodowej - Komisja Ścigania Zbrodni przeciwko Narodowi Polskiemu (www.ipn.gov.pl) | In Polish | → Research institutes → Law, jurisprudence → History |
| IPN | Institut für Biophysik und Nanosystemforschung | In German | → Research institutes → Biochemistry, biophysics |
| IPPA | Indo-Pacific Prehistory Association | In English | → Associations → Prehistory |
| IPPS | International Parallel Processing Symposium | In English | → Congresses → Computer-based techniques → Mathematics |
| IPPT | Instytut Podstawowych Problemów Techniki (www.ippt.gov.pl) | In Polish | → Research institutes → Engineering, technology |
| IPRC | International Pacific Research Center | In English | → Research institutes → International relations → Area studies |
| IPTEA | Internacia Poŝtista kaj Telekomunikista Esperanto-Asocio | In Esperanto | → Associations → Telecommunications → Transport and postal services |
| IQSA | International Qajar Studies Association | In English | → Associations |
| IRAM | Institut de Radioastronomie Millimétrique | In French | → Research institutes → Astronomy |
| IRAS | Interreligiöse Arbeitsgemeinschaft in der Schweiz | In German | → Associations → Religion, theology |
| IRAS | Istituto Spezzino Ricerche Astronomiche | In Italian | → Research institutes → Astronomy |
| IRCAM | Institut de Recherche et Coordination Acoustique/Musique (www.ircam.fr) | In French | → Research institutes → Music → Acoustical engineering |
| IRCCS | Istituto di Ricovero e Cura a Carattere Scientifico | In Italian | → Research institutes → Research policy |
| IRCCyN | Institut de Recherche en Communications et Cybernétique de Nantes (www.irccyn.ec-nantes.fr) | In French | → Research institutes → Telecommunications → Electronics |
| IRCICA | Research Centre for Islamic History, Art and Culture | In English | → Research institutes → Islam → Arts → History → Civilization, culture, progress |
| IrDA | Infrared Data Association | In English | → Associations → Telecommunications |
| IREA | Irana Esperanto-Asocio | In Esperanto | → Associations |
| IREM | Institut de Recherches sur l'Enseignement des Mathématiques | In French | → Research institutes → Education → Mathematics |
| IRES | Institut de Recherches Économiques et Sociales | In French | → Research institutes → Social sciences → Economics |
| IRESCO | Institut de Recherche sur les Sociétés Contemporaines | In French | → Research institutes → Sociology |
| IRESCO | Institut de Recherche Européen en Sociologie et Socio-économie | In French | → Research institutes → Sociology → Economics |
| IRI | Institut de Recherche et d'Innovation (www.iri.centrepompidou.fr) | In French | → Research institutes → Research policy → Civilization, culture, progress |
| IRIS | Inter-Regiona Internacia Semajno | In Esperanto | → Congresses |
| IRIS | Institut des Relations Internationales et Stratégiques (www.iris-france.org) | In English | → Research institutes → International relations |
| IRIS | Incorporated Research Institutions for Seismology (www.iris.edu) | In English | → Research institutes → Seismology, earthquakes |
| IRIT | Institut de Recherche en Informatique de Toulouse | In French | → Research institutes → Computer science |
| IRIT | Institut de Recherche Informatique de Toulouse (www.irit.fr) | In French | → Research institutes → Computer science |
| IRIZ | International Research Institute for Zen Buddhism (http://iriz.hanazono.ac.jp) | In English | → Research institutes → Buddhism |
| IRPI | Institut de Recherche en Propriété Intellectuelle (www.irpi.ccip.fr) | In French | → Research institutes → Artistic property |
| IRRI | International Rice Research Institute (www.irri.org) | In English | → Research institutes → Agricultural sciences |
| IRSC | Instituts de recherche en santé du Canada (www.cihr.ca) = CIHR | Canadian Institutes of Health Research | In English |
In French | → Research institutes → Biological sciences → Medicine |
| IRSEA | Institut de Recherche sur le Sud-Est Asiatique (www.univ-provence.fr/irsea/) | In English | → Research institutes → Area studies |
| IRSN | Institut de Radioprotection et de Sécurité Nucléaire | In French | → Research institutes → Nuclear technology |
| IRT | Institut für Rundfunktechnik (www.irt.de) | In German | → Research institutes → Telecommunications |
| IS | Internacia Seminario | In Esperanto | → Congresses |
| ISA | International Sociological Association | In English | → Associations → Sociology |
| ISAE | Internacia Scienca Asocio Esperantista | In Esperanto | → Associations → Mathematics and natural sciences |
| ISAFIS | Indonesian Student Association for International Studies | In English | → Associations → Higher education, universities |
| ISBS | Internationales Symposium für Biomechanik im Sport | In German | → Congresses → Biological sciences → Sport, physical exercises |
| ISC | International Seismological Centre (www.isc.ac.uk) | In English | → Research institutes → Seismology, earthquakes |
| ISDP | Institute for Security & Development Policy (www.isdp.eu) | In English | → Research institutes → Politics → Development |
| ISE | Internacia Semajnfino Esperantista | In Esperanto | → Congresses |
| ISEGI | Instituto Superior de Estatística e Gestão de Informação | In Portuguese | → Research institutes → Statistics |
| ISEM | Institut des Sciences de l'Évolution de Montpellier | In French | → Research institutes → Biological sciences |
| ISER | Institute for Social and Economic Research | In English | → Research institutes → Demography, statistics, sociology → Economics |
| ISIR | Institut des Systèmes Intelligents et Robotique | In French | → Research institutes → Mechanical engineering → Electronics |
| ISIR | Institut für Statistik und internationale Registrierungen | In German | → Research institutes → Statistics |
| ISIR | Institut des Systèmes Intelligents et de Robotique | In French | → Research institutes → Artificial intelligence → Electrical engineering → Engineering, technology |
| ISL | Inertial Systems Laboratory | In English | → Research institutes → Mechanical engineering |
| ISM | Institut des Sciences Moléculaires | In French | → Research institutes → Biochemistry, biophysics |
| ISME | International Symposium on Microbial Ecology | In English | → Congresses → Ecology |
| ISOPT | International Symposium on Ocular Pharmacology and Therapeutics | In English | → Congresses → Pharmacology, toxicology → Ophtalmology |
| ISP | Instytut Studiów Politycznych | In Polish | → Research institutes → Politics |
| ISR | Instituto de Sistemas e Robótica | In Portuguese | → Research institutes → Electrical engineering |
| ISRA | Islamic Research Academy | In English | → Academies → Islam |
| IST | Istituto Scientifico Tumori | In Italian | → Research institutes → Oncology |
| ISTA | International Seed Testing Association | In English | → Associations → Agricultural sciences |
| ISV | Institut des Sciences du Végétal | In French | → Research institutes → Biological sciences → Botany |
| ISVMA | Illinois State Veterinary Medical Association (www.isvma.org) | In English | → Associations → Veterinary medicine |
| ITAA | Information Technology Association of America | In English | → Associations → Computer science → Telecommunications |
| ITASEAS | Italian Association for Southeast Asian Studies | In English | → Associations → Area studies |
| ITI | Instituto Tecnológico de Informática (www.iti.upv.es) | In Spanish | → Research institutes → Computer science |
| ITQB | Instituto de Tecnologia Química e Biológica | In Portuguese | → Research institutes → Biological sciences → Chemical technology |
| ITU | Institut für Transurane | In German | → Research institutes → Nuclear, atomic, and molecular physics → Nuclear technology |
|