The United States has one of the world’s largest global aluminum markets and a large domestic industry, with U.S. producers participating in each stage of the aluminum manufacturing value chain. This report, the third in a series of reports on the U.S. aluminum and steel industries intended to inform border pollution measure (BPM) policies under development in the United States, provides background on the U.S. aluminum industry, market, and trade. This report covers the unwrought and wrought aluminum segments of the aluminum industry in the United States (Box ES1).