There is a lot of economic literature on the trade effects (trade creation, trade diversion, intraindustrial specialisation) of the integration processes. One of the most analyzed integration processes is the European case, which has been the aim of many studies because its long evolution and depth. This work aims at analysing the tendencies regarding the case of the North American Free Trade Agreement (NAFTA). This process has been less studied than the European one because its shorter evolution. In this sense, we try to verify the existence of trade creation and/or trade diversion effects along with the pattern of intraindustrial specialization, from the perspective of the Mexican economy (1993-2007). Finally, we emphasize the importance of the foreign investments (mainly USA) explaining the new tendencies and trade patterns.