This part concerns specific rules and concepts in the field of international humanitarian law (IHL). Some argue that IHL in its modern juridical-technocratic version is a rather anti-theoretical and at times even anti-intellectual discipline. 1 All modern theories of jurisprudence arguably need to include an understanding of or theory on change. 2 The next sections present different ways of observing and analysing change. It is a spectrum ranging from internal and agency-based to external and structural explanations and perspectives. At the end of this introduction, an attempt will be made to describe how IHL as a system allows room of manoeuvre for states and other actors, including exploitation due to legal gaps and fault lines.