| Abbreviation | Definition |
|---|---|
| IMGA | International Masters Games Association |
| IMGA | Iowa Meat Goat Association |
| IMHA | Indonesian Mental Health Association |
| IMHA | International Maritime Health Association |
| IMHA | International Maritime History Association |
| IMHA | International Milk Haulers Association |
| IMIA | International Map Industry Association |
| IMKA | International Matayoshi Kobudo Association |
| IMLA | Intermediary Mortgage Lenders Association |
| IMLA | International Maritime Lecturers Association |
| IMLA | International Media Lawyers Association |
| IMLA | Irish Maritime Law Association |
| IMMA | International Motorcycle Manufacturers Association |
| IMMAA | International Media Management Academic Association (Saarbrucken, Saarland, Germany) |
| IMMAA | International Mixed Martial Arts Association |
| IMMAA | Iowa Mennonite Mutual Aid Association |
| IMMAJ | International Mariners Management Association of Japan |
| IMMAP | Internet and Mobile Marketing Association of the Philippines |
| IMOA | International Mercury Owners Association |
| IMPA | Idaho Milk Processors Association |