Mandatory investor-state mediation (ISM) as a pre-condition to arbitration is the way forward for rebalancing the investor-state dispute settlement (ISDS) regime and tackling its widely criticised shortcomings. Presenting a comprehensive doctrinal analysis of ISDS clauses of dozens of treaties, this book reveals that simply offering ISM in a voluntary format will not increase its utilisation. In this volume, Ana Ubilava further debunks four common arguments and misconceptions against mandatory ISM through an innovative empirical analysis of over 600 investor-state arbitration cases. She also offers recommendations for incorporating mandatory ISM in ISDS as a precondition to arbitration aimed at international policymakers.