Abstract
Although, in arbitration, usages are everywhere, many practitioners are not aware of their existence. However, they are involved in every step of the arbitral proceeding. Before the making of the decision, procedural usages enable the organization of a sound and precise regulation of the arbitral proceeding. At the time of the making of the decision, substantial usages ensure to come to the most adequate decision, in order to put an end to the dispute. Hence, they can be a very useful tool, that would be an alternative to national Laws