major American manufacturer of pulp and paper products, including printing paper, specialty paper products, packaging materials, lumber, and manufactured construction materials. It also is one of the world's largest private owners of timberland, with millions of acres of forest holdings in the United States, Canada, Russia, New Zealand, and Brazil. Headquarters are in Stamford, Connecticut.

The original company was established as International Paper Company in 1898 in a merger of 20 paper mills in the northeastern United States. It was subsequently acquired in 1941 by International Paper and Power Corporation, which then assumed the original name. International Paper has a history of acquisitions and mergers but has tended to concentrate on paper and lumber production. In 1986 International Paper acquired the Hammermill Paper Company, a manufacturer of printing papers and a large paper marketer and distributor. The company broadened its interest in paper and packaging products with the purchases of competitors Federal Paper Board Company in 1995 and Champion International (Champion International Corporation) in 2000.

International Paper manufactures a wide variety of paper products for business and industry, including stationery, fine writing and printing papers, and specialty newsprint; packaging products, including paper boxes and bags and plastic containers; and wood products. Its global subsidiaries are active in consumer paper products, wholesale paper distribution, and chemicals made from wood by-products. The company's timberlands—the bulk of which are in the southern, northeastern, and western United States and Canada—supply the raw materials for plants throughout the United States and abroad. As of the early 21st century, International Paper was the largest private landowner in the United States.