In this article Andreas Paulus examines the law applicable to the use of force in occupied territory, which constitutes a good example for the scope and the overlap of legal régimes between peace and armed conflict. International humanitarian law, the law of occupation, human rights law and the jus ad bellum are analysed. He then focuses on "transformative occupations", in which the occupier does not intend to re-establish the previous political régime but to comprehensively modify the interior structure of the State.