Chapter 5 tackles the question of the applicability of belligerent reprisals in non-international armed conflict. After assessing the merits and difficulties associated with previous reflections on the topic, it devises a new methodology to approach the issue. Then, it puts the notion of belligerent reprisals in relation with the two features of inequality of status between States and non-State armed groups, and equality of rights and obligations for parties to non-international armed conflicts. A careful reading of the travaux préparatoires of Additional Protocol II to the 1949 Geneva Conventions upholds an interpretation that links belligerent reprisals with the latter principle, and that places reciprocity at the basis of both the applicability and the purpose of the measure in non-international armed conflicts. The chapter concludes with the impact of this formalization on such key questions as the requirement of imputability to a State of the original IHL violation and the actual features of the principle of equality. It suggests that the focus be shifted to the idea of equilibrium of rights and obligations, and that belligerent reprisals be seen as a key enabler of it.