| ISSN | Independent Simultaneous Sources with Nodes 
| Others |
| ISSN | Individual Simple Standard Number
| Others |
| ISSN | Information Standard Serial Number
| Others |
| ISSN | Integrated Special Services Network
| Others |
| ISSN | Intelligence Specialist Seaman
| Others |
| ISSN | International Society for the Study of Narrative
| Others |
| ISSN | International Society of Sports Nutrition
| Others |
| ISSN | International Standard Serial Number
| Others |
| ISSN | International Standardized Serial Number
| Others |
| ISSN | International Studies Schools Network
| Others |
| ISSN | Interstellar Synchronism Setup Noise
| Others |