This paper examines Mexico's increase in wage inequality using data from household surveys (Encuesta Nacional de Ingreso Gasto de los Hogares de México) produced by the Mexican Institute for Statistics, Geography and Informatics (Instituto Nacional de Estadística, Geografía e Informática). An econometric simulation technique based on Juhn, Murphy, and Pierce (1993) and developed for the household level by Bourguignon, Fournier, and Gurgand (1998) is used to measure the contribution of changes in skill premiums and sector returns to the increase in inequality in Mexican males' wages during the period of analysis. The household surveys used in this paper make it possible to decompose some of the changes in inequality in Mexico after trade reform in the mid-1980s. The regressions and simulation technique confirm that male Mexican wage earners experienced an important increase in skill premiums and a decrease in sector wage premiums after the trade reform. The increase in skill premiums was unequalizing, while the decrease in sector premiums was equalizing.