STS-122 was a NASA Space Shuttle mission to the International Space Station (ISS), flown by the Space Shuttle Atlantis. STS-122 marked the 24th shuttle mission to the ISS, and the 121st space shuttle flight since STS-1.

The mission was also referred to as ISS-1E by the ISS program. The primary objective of STS-122 was to deliver the European Columbus science laboratory, built by the European Space Agency (ESA), to the station. It also returned Expedition 16 Flight Engineer Daniuel M. Tani to Earth. Tani was replaced on Expedition 16 by Leopold Eyharts, a French Flight Engineer representing ESA. After Atlantis' landing, the orbiter was prepared for STS-125, the final servicing mission for the Hubble Space Telescope.

The original target launch date for STS-122 was 6 December 2007, but due to engine cutoff sensor (ECO) reading errors, the launch was postponed to 9 December 2007. During the second launch attempt, the sensors failed again, and the launch was halted. A tanking test on 18 December 2007 revealed the probable cause to lie with a connector between the external tank and the shuttle. The connector was replaced and the shuttle launched during the third attempt on 7 February 2008.

STS-122 was the ISS Assembly Flight 1E, which delivered the European Columbus laboratory module to the station, along with the Biolab, Fluid Science Laboratory (FSL), European Drawer Rack (EDR), and European Physiology Modules (EPM) payloads.

STS-122 also carried the Solar Monitoring Observatory (SOLAR), the European Technology Exposure Facility (EuTEF), and a new Nitrogen Tank Assembly, mounted in the cargo bay of an ICC-Lite payload rack, as well as a spare Drive Lock Assembly (DLA) sent to orbit in support of possible repairs to the starboard Solar Alpha Rotary Joint (SARJ), which was malfunctioning.

Several items were returned with Atlantis: A malfunctioning Control Moment Gyroscope (CMG) that was swapped out with a new one during STS-118, and the empty Nitrogen Tank Assembly was placed in the orbiter's payload bay, along with a trundle bearing from the Starboard SARJ that was removed during an EVA performed by Expedition 16.

The external tank (ET-125) arrived at the Kennedy Space Centre on 14 September 2007, after traveling by barge from the Michoud Assembly Facility in Louisiana. The external tank was then transferred to the Vehicle Assembly Building (VAB) to be inspected, and have the Liquid oxygen feedline bracket modified, before being mated to the solid rocket boosters on 17 October 2007.

The external tank was attached to the solid rocket boosters on 18 October 2007, and Atlantis moved to the VAB on 3 November 2007. With the entire stack placed upon the mobile launcher platform, Atlantis moved to launch pad 39A on 10 November 2007, and the Columbus module was loaded into the orbiter's payload bay on 12 November. The terminal countdown demonstration test was completed on 20 November 2007.

Following the final Flight Readiness Review on 30 November 2007, NASA managers announced that Atlantis was ready to fly, and the launch date of 6 December 2007 was confirmed. The crew arrived at Kennedy Space Centre on 3 December 2007, to prepare for the first launch attempt on 6 December 2007