Transposition, docking, and extraction (often abbreviated to transposition and docking) was a maneuver performed during Apollo lunar landing missions from 1969 to 1972, to withdraw the Apollo Lunar Module (LM) from its adapter housing which secured it to the Saturn V launch vehicle upper stage and protected it from the aerodynamic stresses of launch. The maneuver involved the command module pilot separating the Apollo Command and Service Module (CSM) from the adapter, turning the CSM around, and docking its nose to the Lunar Module, then pulling the combined spacecraft away from the upper stage. It was performed shortly after the trans-lunar injection maneuver that placed the Apollo spacecraft on a three-day trajectory to the Moon. The docking created a continuous, pressurized tunnel which permitted the astronauts to transfer internally between the CSM and the LM.
The same maneuver was performed on the 1975 Apollo–Soyuz Test Project (ASTP) mission to extract a special docking module used to connect the Apollo Command Module with the Soyuz spacecraft.