In the context of the 20th anniversary of the North America Free Trade Agreement (NAFTA), this article will analyze its Chapter XI: Investor- State Dispute Settlement. Chapter XI embodies the investor’s real and practical experience under NAFTA rules. An examination of the historical record demonstrates that Mexican lawyers have been passive participants in defending investors’ rights. On the other side of the coin, Mexican investors have not been active participants in NAFTA’s Chapter XI, in contrast to Canadian and US investors. Finally, Mexico’s experience in international arbitration has not always been negative, but Mexico has been criticized for a lack of transparency and due process for foreign investors.