Combatants are obliged to distinguish themselves from the civilian population while they are engaged in an attack or in a military operation preparatory to an attack. In accordance with the generally agreed practice of states, members of regular armed forces shall wear their uniform. Combatants who are not members of uniformed armed forces nevertheless wear a permanent distinctive sign visible from a distance and carry their arms openly. 

Combatants are all persons who may directly participate in combat operations, e.g. the members of the armed forces as well as militias and volunteer corps forming part of the armed forces.

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Only combatants are entitled to take part in combat operations and cannot be punished for doing so. In contrast, other persons, e.g. mercenaries, can be punished.

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If combatants fall into the hands of the enemy, they become prisoners of war.

They may not be held responsible for their participation in permitted acts of war. Violations of international law, however, may be punished according to the law of the detaining power.