Field marshal is the second most senior military rank, ordinarily senior to the general officer ranks, but junior to the rank of Generalissimo. Usually, it is the highest rank in an army, and as such, few persons are ever appointed to it. It is considered as a five-star rank (OF-10) in modern-day armed forces in many countries. Promotion to the rank of field marshal in many countries historically required extraordinary military achievement by a general. However, the rank has also been used as a divisional command rank and also as a brigade command rank. Examples of the different uses of the rank include Afghanistan, Austria-Hungary, Pakistan, Prussia/Germany, India and Sri Lanka for an extraordinary achievement; Spain and Mexico for a divisional command ; and France, Portugal and Brazil for a brigade command.

Generalissimo is a military rank of the highest degree, superior to field marshal and other five-star ranks in the states where they are used.