Special Agreement under International Humanitarian Law is a modest contribution in the field of international humanitarian law. The book analyses the concept of Special Agreement contemplated in the Geneva Conventions of 12 August 1949. It provides analysis into the purposes, form, types, scope, nature, duration and implications of special agreements. Similarly, it discussed possible reasons why States and armed groups conclude or refuse to conclude special agreements; some of the fundamental issues in International Humanitarian Law contained in previous special agreements, how they have worked or failed to work and whether they have impacted on the behaviour of the parties as well as how the agreements have played a role in judicial decisions. Through varieties of agreements studied in both international and non-international armed conflict, it pointed out the concretisation of some International Humanitarian Law rules into customary international law especially in non-international armed conflicts.