These concourses were constructed in 1983 and designed by Hellmuth, Obata and Kassabaum. The two concourses have 22 gates each, numbered C1–C28 and D1–D32, with odd-numbered gates on the north side of the building and even numbered gates on the south side. Concourse C composes the eastern half of the terminal and Concourse D composes the gates on the west half of the terminal. The C/D concourses were given a face lift in 2006 which included light fixture upgrades, new paint finishes, new ceiling grids and tiles, heating and air conditioning replacement, and complete restroom renovations.