The growth in the amount of international arbitrations, the value of the disputes and expenses invested into the arbitral proceedings have escalated the pressure to succeed in dispute. The arbitrators face to guerrilla tactics or threats of annulment of arbitral awards based on the violation of a right to a due process. Soft law regulating the arbitral procedure endowers the effectives of the arbitration, however, in the recent years the critical voices can be heart which warn against overregulation and its judicialization. On the following pages the impact of the soft rules prescribing the arbitral proceeding on the effectiveness of the international commercial arbitration is examined. Firstly the author deals with the right to a fair trial and the discretionary power of arbitrators in the framework of the notion of soft law and then the binding character of this soft law is determined. The aim of this article is to answer the question whether the regulation of the arbitral proceedings by soft law is still welcomed or if it represents a threat for the discretionary powers of the arbitrator and arbitration as such.