While reliable statistics are not available, the 1989 Treaty between Mexico and Spain on the recognition and enforcement of judicial rulings and arbitral awards appears to be little used today. This article specifically examines and comments on the negative aspects of the Treaty that may be problematic in the recognition and enforcement of arbitral awards, demonstrating the need to update and adapt it to modern trends in arbitration today. The article begins with a brief history of the Treaty (noting that it was entered into, significantly, before Spain and Mexico enacted the UNCITRAL Model law), followed by an analysis of several provisions of the Treaty and their applicability or interpretation.