An officer of one-star rank is a senior commander in many of the armed services holding a rank described by the NATO code of OF-6. The term is also used by some armed forces which are not NATO members. Typically, one-star officers hold the rank of commodore, flotilla admiral, brigadier general, brigadier, or in the case of those air forces with a separate rank structure, air commodore.
Officers of one-star rank are either the most junior of the flag, general and air officer ranks, or are not considered to hold the distinction at all. Specifically, in many navies, one-star officers are not considered to be flag officers, although this is not always the case. The army and air force rank of brigadier general is, by definition, a general officer rank. However, the equivalent rank of brigadier is usually not designated as a general officer. The air force rank of air commodore is always considered to be an air-officer rank.
- Commodore (Royal Canadian Navy one-star-equivalent rank)
- Brigadier-general/brigadier-général (Canadian Army and Royal Canadian Air Force one-star-equivalent rank)
The maple leaf appears with St. Edward's crown and crossed sabre and baton.
Army and Air Force:
- Brigadegeneral (brigadier general)
- Generalarzt ("surgeon general")
- Generalapotheker ("pharmacist general")
- Brigadier general (Philippine Army one-star rank)
- Brigadier general (Philippine Air Force one-star rank)
- Commodore (Philippine Coast Guard one-star rank)
- Commodore (Philippine Navy one-star rank)
- Police brigadier general (Philippine National Police one-star rank)
- Fire chief superintendent (Bureau of Fire Protection one-star rank)
- Jail chief superintendent (Bureau of Jail Management and Penology one-star rank)
In the modern naval services of Belgium, Denmark, Finland and Sweden, the one-star rank is flotilla admiral.