This book consists of two main parts. The first section is dedicated to the study of the system of annulment of verdicts in ICSID. The second section deals with the necessity, reasons, and how to create a mechanism for ICSID's tribunal's appeal, given the relative success of World Trade Organization Appellate Board; In this section, in the light of the previous discussions, the necessity of creating an ICSID's appellate board has been explored, the reasons for the need to create an ICSID reconsideration system are presented.