Nowadays it is no longer possible to understand trade only as the exchange of goods for goods between different countries; the development of new forms of productive organisation such as global market chains, i.e. the location in various geographical areas of different segments of a single production chain, has given rise to another type of trade such as Intra-Industry Trade (IIC), i.e. trade within the same industry. The work presented below seeks to analyse the competition between the US and China in the Mexican auto parts sector, based on the IIC flows between Mexico and these countries, and thus understand the dynamics that have emerged within this Mexican industry between 2000 and 2013.