This study aims to examine the substantive applicable law in different arbitral tribunals, especially the ICSID and the Iran-US Claims Tribunal. Additionally it examines the role of international law and whether it has supremacy over national laws. To that end, this publication is mainly based on case studies, the most cited ICSID and Iran-US Claims Tribunal cases. Furthermore, it addresses scientific works on this topic with regard to various arbitration rules and in particular to the applicable law.

Niki Nozari was born in Tehran. She passed her First Iranian State Examination in Law after studying at the University of Shahid Beheshti, Tehran, where she also received her Master of Laws. She completed her legal internship in Tehran until graduating with the Second State Examination in Law.