Acquisition of rapid calibration of reaching with displacement prisms was studied. Participants reached rapidly to place a stylus in a hole. Blocks of trials with and without a 10 degree displacement prism were alternated over sessions on three days. Movement times (MT), peak velocities (PV) and path length (PL) of reaches were measured. MT and PL increased at the beginning of blocks and then decreased over trials within blocks. The rate of adaptation within blocks did not change over blocks or days. Initial increases in MT and PL at the beginning of blocks gradually decreased. Progressively fewer trials were needed to reach criterion MTs. Calibration was nearly immediate by day three. Visual information used for calibration is discussed.