Gary S. Elbow is Professor of Geography at Texas Tech University, where he has taught since 1970. In 1972, he received his Ph.D. from the University of Pittsburgh. He has approximately 35 years of experience in regional, Latin American, human and urban geography as well as geography. He is also a critic for AP Central`s Teachers` Resource Catalog for AP Human Geography. The North Atlantic Free Trade Agreement (NAFTA) was signed in 1994 between Canada, the United States and Mexico. The primary objective of the treaty was to remove barriers to trade between the three countries and to offer reciprocal benefits to stimulate growth. Much of this trade is complemented. This means that it does not compete with similar products from the importing country. There are, however, important exceptions. Mexico is the country where maize was domesticated for the first time and maize remains an important part of the country`s diet and culture. But much of the Mexican maize is produced in tiny farms using old techniques.

For example, Mexico`s maize production is much less efficient than highly mechanized maize farming in the United States. Imports of maize from the United States have caused the price of maize in Mexico to fall, causing problems for Mexican maize producers, many of whom depend on maize for both their family subsistence and the low cash income they receive (Weiner 2002). It is clear that not all sectors of Mexican agriculture have benefited from free trade. International trade agreements, agricultural subsidies and responses to genetic modification technology all have global implications for agriculture. Some of these effects are positive, such as increased productive activity on farms or the ability to ship food from surplus areas to areas in need. However, the globalization of agriculture also has drawbacks. Local farmers may not be able to compete in the international market. The unintended consequences of technological innovation can lead to irreversible environmental changes, and even if they do not, public response to innovation may limit their potential for acceptance.