Successful ship handling depends upon acquiring the right information, making the right decisions and performing the right manœuvres; this paper concentrates upon the last of these. Manœuvring here is taken to include starting, stopping and steering. The ship is a vehicle with remarkably low resistance to motion; merchant ship drags commonly lie in the range one-hundredth to one-thousandth of the all-up weight force. This is comparable with that of a railway wagon (say 1/500 of its weight) and the low drag accounts in part for the ship's extreme economy as a carrying machine.