Packaging Corporation of America manufactures containerboard products and uncoated freesheet paper in North America. Its operates eight mills and 90 corrugated manufacturing plants. Its containerboard mills produce linerboard and corrugating medium (paper used in the production of corrugated products). Its corrugated products plants produce conventional shipping containers used to protect and transport manufactured goods. Packaging Corporation of America was founded in 1867 and is headquartered in Lake Forest, IL.