An econometric model representing the United States, Mexico and Caribbean nations melon sectors was estimated to analyze the primary economic forces influencing Mexico's competitiveness in the U.S. winter melon market, a period when about two-thirds of U.S. consumption is imported. Results show peso-devaluation to be important in the short-run and yield-enhancing technology to be important in the short- and long-run. Increased rates of growth in Mexican yields were about six times more effective at increasing market share than NAFTA provisions which phase-out U.S. tariffs. An accelerated rate of growth in Mexican per capita income was found to reduce melon exports about 75% while higher wages would reduce exports about 20% in the long-run.