The quarterly empirical relationship between Mexican manufacturing labor productivity and salaries 1993-2015 is examined for causality and whether first order labor market equilibrium is evident. An equilibrium would mean salaries and labor productivity are cointegrated. Wages above productivity levels may lead to calls for government intervention in the labor market. Federal quarterly data cover the nine main divisions of the manufacturing sector (old classification) as well as manufacturing overall. We use two series: labor productivity and average salaries with adjustment for inflation using the US consumer price index (2010 = 100). The time series is from 1993.1 to 2015.3. Standard cointegration analysis with structural change is applied with structural breaks hypothesized in 2008 with the Great Recession and 1995 with the Peso crisis. Tests for stationarity are applied to potentially correct for problems using first differences. Results indicate a statistically significant and negative relationship between labor productivity and salaries early in the sample period that becomes positive after structural changes. Salaries are more sensitive to events and volatile while productivity exhibits stable growth during 1993-2015. Salaries were impacted by both the 1995 Peso crisis and the Great Recession (2008) but productivity was only impacted by the latter. Higher labor productivity has not been rewarded with higher salaries suggesting Mexican manufacturing workers are underpaid. The firms where they work therefore have excess profits that can be used for investment and/or pay raises. Only the Timber and Metals divisions are found to not have salaries and productivity cointegrated. Government intervention in the form of wage setting or wage protection to protect firms from higher labor costs is unnecessary as firms are underpaying their workers. The government should reduce its role in the manufacturing labor markets. Foreign firms can hire underpaid workers away from domestic industry and take advantage of the labor market disequilibrium. Unions can insist on higher salaries to match their highly productive members work.