Operational for more than 100 years, USG Corporation is a manufacturer and distributor of construction materials. Its products include gypsum wallboards, joint compounds, cement boards and accessories, gypsum fiber panels, poured gypsum underlayments and various construction plaster products. USG Corporation, also known as United States Gypsum Corporation, has several subsidiaries, including United States Gypsum Company, USG Interiors, L&W Supply Corporation, CGC and USG International. USG Corporation distributes products through its own locations, specialty wallboard distributors, building material dealers, home improvement centers, retailers and contractors. It also manufactures and markets interior systems products, including ceiling tiles and grids. Headquartered in Chicago, USG Corporation employs more than 14,000 people in over 30 countries. It also maintains a location in Southard, Okla.