Koppers Holdings is a holding company. Through its subsidiaries, the company is a provider of treated wood products, wood treatment chemicals, and carbon compounds. The company operates three principal business segments: Railroad and Utility Products and Services, which supplies railroad crossties to the North American railroads; Performance Chemicals, which manufactures and supplies water-based wood preservatives and wood specialty additives to treaters who supply the residential, agricultural and industrial pressure-treated wood markets; and Carbon Materials and Chemicals, which processes coal tar into a variety of products, including creosote and other related railroad products.