The Current Employment Statistics (CES) program of the Bureau of Labor Statistics (BLS), surveys approximately 490,000 establishments in order to provide detailed industry data on employment, hours, and earnings of workers on nonfarm payrolls. The authors have been researching the use of CES survey data to produce industry estimates by firm size. This paper first details research to develop methodologies for producing CES estimates by firm size. This includes defining size classes, determining firm size, additivity across size classes to the industry estimates, forecasting net birth/death residuals, seasonal adjustment, and the creation of a historical series of CES size class estimates. Next, the paper covers several issues addressed by the developed methodology. CES considered the adequacy of the sample for size class estimates along with movements of firms between size classes to understand how this might impact estimate reliability. Finally, the paper analyzes several quality measures of the time series produced in the research. The research suggests that the introduction of size class estimates would provide a valuable and reliable addition to what is currently published by the CES program.