Trade flows between the United States and Mexico get most of the headlines, but the investment relationship underpinning them is equally substantial — and has grown dramatically over the past quarter century. U.S. foreign direct investment in Mexico stood at $159.2 billion in 2024, up from $37.2 billion in 1999. That 328% increase reflects a sustained commitment by American firms to production facilities, distribution networks, and service operations south of the border.