Vice admiral is the next higher rank. Depending on the navy involved, the next lower rank is either commodore or captain. Some navies treat commodore as a temporary position rather than an actual rank, while in others, it is the lowest level of flag officer.
The U.S. Navy has oscillated between having distinct ranks of rear admiral (two star, pay grade O-8) and commodore (one star, pay grade O-7), and, at other times, having "rear admirals of the upper half" and "rear admirals of the lower half." All rear admirals wore two stars, but those of the lower half were paid at the one-star rate. Rear admirals of the lower half tended to annoy one-star army, air force, and marine brigadier generals who were actually senior in date of rank, but wore the apparently junior insignia.
In modern militaries, typical command assignments at this level would be a task group or small task force, a major shore base, or a high level of staff responsibility, such as the chief of staff of a fleet or a directorate within a national naval staff.
- NATO codes for grades of military personnel: Agreed English texts, 1992, NATO Standardization Agreement (STANAG) 2116