| Acronym | Definition |
|---|
| ISG | Iraq Study Group |
| ISG | Iraq Survey Group |
| ISG | International Steel Group |
| ISG | Idle Stop and Go (Kia Motors Corporation) |
| ISG | Information Storage Group |
| ISG | Information Services Group |
| ISG | Internet Services Group |
| ISG | Integrated Starter Generator |
| ISG | Intelligent Services Gateway |
| ISG | Integrated Services Group (various locations) |
| ISG | Integrated Starter/Generator |
| ISG | Instructional Support Group (various locations) |
| ISG | Infinite Sword Glitch (gaming) |
| ISG | Integrated Security Gateway |
| ISG | Information Systems Group |
| ISG | Information Systems Group (IBM) |
| ISG | Integrated Solutions Group (formerly Computerland) |
| ISG | Immune Serum Globulin |
| ISG | Incident Support Group (US FEMA) |
| ISG | Intermarket Surveillance Group |
| ISG | Intelligent Services Gateway (Cisco) |
| ISG | Infrastructure Steering Group |
| ISG | Investment Services Group |
| ISG | International Security Group, Inc. (Washington, DC) |
| ISG | Indicators' Sub-Group (Social Protection Committee; European Commission) |
| ISG | Industry Steering Group |
| ISG | Individual and Small Group (medical insurance) |
| ISG | Ichthyosis Support Group |
| ISG | Interoperability Steering Group (US DoD) |
| ISG | Internet Safety Group (New Zealand) |
| ISG | Integrated Services Gateway (Sprint) |
| ISG | International Series Gold (Association of Tennis Professionals; tournaments) |
| ISG | Infiniti Systems Group (various companies) |
| ISG | Iraq Stabilization Group (US State Department) |
| ISG | Instrument Support Group |
| ISG | Infrastructure Support Group |
| ISG | Internet Support Group (Deutsche Bank) |
| ISG | Information Storage Group (HP) |
| ISG | Intelligence Support Group |
| ISG | Incoming Service Grouping |
| ISG | Ilio-Sakral-Gelenk (German: Ilio-sacral-joint) |
| ISG | Information and Support Group |
| ISG | Instant Software Generation |
| ISG | Individual Security Guard |
| ISG | Intersite Gateway |
| ISG | Internal Stable Globalization (psychology) |
| ISG | Information Security Guideline |
| ISG | Immortal Soldiers Gaming Network (gaming) |
| ISG | Intuitive Solutions Group (Ontario, Canada) |
| ISG | Immediate Staffing Group, Inc. (strike staffing firm) |