The growing trend to consider as customary law roles devised to support prefeences and arguments, that cannot otherwise qualify as law, is leading to serious doubts about the real meanulg of international law. This article examines the reasons behind this phennmenon and reflects on means for strengthening the traditional requirements of customary international law so as to ensure that proper law is made. It notes that customary international law cannot depend on the advancement of instrumental goals some times in contradiction with the requirements of a stable legal system. The articles examines in particular the meaning of States practice and opinio juris, the traditional elements for the formation of customary rules. It argues in conclusion that the efforts at reengineering customary law have actually revived its role to an unextpected extent, to the point that the reaction against its manipulation is gradually bringing back international law to its normal balance.