To be effective, and something more than a collection of individuals with weapons, a military unit must be commanded. Commanders are responsible for achieving the unit’s objective, a function that requires them to ensure that subordinates will do as they are told. With this power comes responsibility. In some circumstances commanders can be penalized for the misconduct of subordinates. In the classical model of military justice, commanders played (and in some countries, such as the United States, still play) a powerful role. ‘Military command and military discipline’ considers the powers exercised by commanders in these commander-centric systems—in particular the disposition, or charging, power—and looks at efforts to reform these systems.