This report, conducted by researchers at the Illinois Economic Policy Institute, the University of Illinois Project for Middle Class Renewal, and Occidental College, analyzes the course of unionization in Illinois, in the Chicago metropolitan statistical area (MSA), and in the United States from 2006 to 2015. It is the third annual report of its kind for union members in the Chicago area and in Illinois. The report tracks unionization rates and investigates union membership across demographic, educational, sectoral, industry, and occupational classifications. The study subsequently evaluates the impact that labor union membership has on a worker’s hourly wage in Illinois, in the Chicago MSA, and in America. Additionally, data on labor unions and similar labor organizations are included and analyzed, new for the 2016 version of this report.