This article analyzes how foreign capitals performed in the Mexican economy during the implementation of the Import Substitution Industrialization (ISI) model and Neoliberalism. The State played a larger role in the first model, whereas the private sector on the second one. In the short run, while implementing these two economic models, foreign capitals coming from private international banks and international financial institutions allowed moderate economic growths in Mexico. But, in the long run, they have also led to the accumulation of debt and precipitated Mexico’s economy into deep crisis. To achieve our goals, this paper will revise works of leading intellectuals in the field, and will gather statistical data from the World Bank and the Economic Commission for Latin America and the Caribbean (CEPAL). Consequently, Mexico’s economic development has been determined by the use of outside resources, which, in some cases, have ignited financial crisis.