IRM

• 1RM
• Bureau of Information Resource Management
• IERS Reference Meridian
• IFAST
• IRM (album)
• Illinois Railway Museum
• Illinois Reserve Militia
• Information Rights Management
• Interference reflection microscopy
• Internal Revenue Manual
• International Review of Mission
• Irish Republican Movement
• Iron Mountain Incorporated
• Islamic Republic of Mauritania
• L'Institut Royal Météorologique de Belgique
• Mahan Air
• Zinc oxide eugenol