| Illinois Science Assessment | Academic & Science |
| Ionic Strength Adjuster | Academic & Science |
| International Society of | Academic & Science |
| ISA - The International Society for Measurement and Control | Academic & Science |
| Association Internationale de Sociologie | Academic & Science |
| Asociación Internacional de Sociología | Academic & Science |
| International Society of Andrology | Academic & Science |
| Institution of Surveyors, Australia | Academic & Science |
| Indian Society of Anaesthesiologists | Academic & Science |
| International Society of Audiology | Academic & Science |
| Instrumentation Society of A | Academic & Science |
| Iteration Symmetry and Alternation | Academic & Science |
| International Students Association | Academic & Science |
| Islamic Students Association | Academic & Science |
| International Student Association | Academic & Science |
| International Student Advising | Academic & Science |
| Indian Student Association | Academic & Science |
| Internet Services for Alumni | Academic & Science |
| International Standard Architecture | Academic & Science |
| Interface Studio Architects | Academic & Science |
| International Standard On Auditing | Accounts and Finance |
| International Standard of Auditing | Accounts and Finance |
| Mount Isa | Airport Code |
| Information Systems Audit | Banking |
| Individual Savings Account | Banking |
| International Society of Appraisers | Business |
| International Society of Arboriculture | Business |
| International Sociological Association | Business |
| International Society of Automation | Business |
| Irish Software Association | Business |
| Income Share Agreement | Business |
| International Sales Agent | Business |
| Information Sharing Assessment | Business |
| Income Share Account | Business |
| Industry Sub-sector Analysis | Business |
| Isotechnika Pharma, Inc. | Business |
| International Sugar Agreement | Business |
| Investment Savings Account | Business |
| International Safety Auditors | Business |
| Interoperability Standards Advisory | Business |
| Intelligence And Security Agency | Business |
| Internal Security Agency | Business |
| International Standards on Auditing | Business |
| Santa Isabel, S. A. | Business |
| Instrumentation Systems and Automation | Chemistry |
| In Shaa Allah (at Allah's will) | Community |
| Independent Spiritualist Association | Community |
| In Shaa' Allah (God willing) | Community |
| Internationals Schools Assessment | Community |
| International School of the Americas | Community |
| International Schools Assessment | Community |
| Isaiah | Community |
| Integrity, Soul, and Attitude | Community |
| Instantaneous Self-Assessment | Community |
| Investigative Skills Assessment | Community |
| International Surfing Association | Community |
| Industrial Supply Association | Community |
| International Sign Association | Community |
| International Studies Association | Community |
| International Strabismological Association | Community |
| International Slackline Association | Community |
| Input Signal Amplifier | Computer Hardware |
| Information Sharing and Assessment | Computing |
| Internal Security Act | Computing |
| Internet Server Application | Computing |
| Internet Security Association | Computing |
| Internet Service Api | Computing |
| Internet Services Administrator | Computing |
| Information Security and Assurance | Computing |
| Independent Stations Algorithm | Computing |
| Identifier Splitting Algorithm | Computing |
| Informix Server Administrator | Computing |
| Itanium Solutions Alliance | Computing |
| Interactive Services Association | Computing |
| Integrated Service Adapter | Computing |
| Information Security Auditor | Computing |
| Information Sharing Agreement | Computing |
| Information Science Abstract | Computing |
| Informix System Administrator | Computing |
| Instrumentation Society of America | Electronics |
| Idle Speed Actuator | General |
| Intelligent Speed Assistance | General |
| Iveco South Africa | General |
| International Symbol of Access | General |
| Intelligent Speed Advice | General |
| International Security Alliance | General |
| Interplanetary Strategic Alliance | General |
| Independent Savings Account | General |
| Instruction Stable Alert | General |
| International Studies Abroad | General |
| Integrated Systems Analysts | General |
| Inside Surface of Assembly | General |
| Industrial Services of America | General |
| Internal Security Assessor | General |
| Individual Savings Accounts | General |
| Inside Sales Advisor | General |
| Institut de Selection Animale | General |
| Interim Service Agreement | General |
| Institute De Selection Animale | General |
| Institut de Sélection Animale | General |
| Integrated Starter Alternator | General |
| Incline Start Assist | General |
| Information Systems Architecture | Governmental |
| International Federation of the National Standardizing Associations | Governmental |
| Institute Of Self Actualization | Governmental |
| Institute for Self Actualisation | Governmental |
| Intelligent Speed Adaptation | Governmental |
| International Seabed Authority | Governmental |
| Independent Safeguarding Authority | Governmental |
| ISARDA | Indian Railway Station |
| Industry Standard Architecture | Information Technology |
| Instruction Set Architecture | Information Technology |
| Industrias Subsidiarias de Aviación | International |
| International Strategic Analysis | International |
| It's So Annoying | Internet |
| Internet Security Alliance | Internet |
| Independent Safety Assessor | Jobs |
| Interstitial Acute | Medical |
| Intrinsic Sympathomimetic Activity | Medical |
| Intensive Support Amount | Medical |
| International Standardization Agreement | Military and Defence |
| Inter-service Agreement | Military and Defence |
| Intelligence Support Activity | Military and Defence |
| Internet Security and Acceleration | Networking |
| Mount Isa, Australia | Regional |
| Interim Stowage Assembly | Space Science |
| Initial Sun Acquisition | Space Science |
| Iowa Soccer Association | Sports |
| International Slacklining Association | Sports |
| Innovative Slot Allocation | Telecommunication |
