The UN's ‘classical’ peace-keeping operations fall somewhere between Chapters VI and VII of the Charter, and therefore do not coincide with the 1945 concept of UN 'action'. Therefore such operations should be juridically assessed as a practice which has developed with its own characteristics. However, a number of legal principles may be derived from this long-standing practice, which may be considered as falling under customary law, even if the United Nations has not yet reached the stage of adopting a codification of such principles.