Document prepared by the International Committee of the Red Cross (30IC/07/8.3)
This report is being submitted pursuant to Resolution 1 of the 28th International Conference of the Red Cross and Red Crescent.
Treaty law and customary law are the main sources of international law. In the area of international humanitarian law, treaty law is well developed but its application is limited to States that have ratified the treaties in question, and to armed opposition groups within those States. Customary international humanitarian law, on the other hand, is binding on all States but its content is less clear because it is not written down as such. Customary international law is created by widespread, representative and uniform practice among States. Its rules, as a result, can only be determined on the basis of extensive research into that practice.
The study on customary international humanitarian law which the ICRC published in 2005 is the first of its kind. Undertaken at the request of the 26th International Conference of the Red Cross and Red Crescent in December 1995, it was completed nearly 10 years later, following extensive research and widespread consultation of experts.