| Abbreviation | Definition |
|---|---|
| ISP | Intermediate Start Position |
| ISPAL | Institute for Sport, Parks and Leisure (UK) |
| ISPN | Ingrum Sports Production Network |
| ISPS | International Shogi Popularization Society |
| ISPS | International Sports Promotion Society |
| ISPT | Institute for Sustainable Process Technology |
| ISPT | International Stadiums Poker Tour |
| ISQ | Ice Skating Queensland |
| ISR | International Sports Relations |
| ISRA | Illinois Squash Racquets Association |
| ISRA | Illinois State Racquetball Association |
| ISRA | International Sim Racing Association |
| ISS | Improving Soccer Sportsmanship |
| ISS | Instructional Sports Skills |
| ISS | International Superstar Soccer |
| ISSA | International Sports Science Association |
| ISSF | International Shooting Sports Federation |
| ISSL | Inter-Societies Soccer League |
| ISSM | Institute of Sports Sciences and Medicine |
| ISSO | International Side Saddle Organization |