In some maritime countries of Europe this word was formerly, and is to some extent even now, used to designate an officer of a vessel having the charge of the ship's course. By general usage the term is now applied to a person not belonging to a ship, who conducts it into or out of a harbor, or over shoals, or wherever the navigation requires superior local knowledge. The office is regulated by law in most civilized countries. The English statutory provisions on this subject are to be found in the merchants' shipping act, 1854, 17 and 18 Victoria, c. 104, §§ 330-388. In the United States an act of congress authorizes the several states to make their own pilotage laws; and such laws have been accordingly enacted by all the seaboard states. These laws generally provide for the appointment of commissioners who are invested with power to make all needful rules and regulations on the subject. While a pilot is on board a vessel within the pilot grounds, he has the control of it, and is answerable for any injury which may happen to it through his fault; and this liability was carried to such an extent by the early maritime law of some European countries, that the pilot, if unable to render full satisfaction, atoned for his negligence with his life.

While the pilot is on board the power of the master of the vessel is not wholly superseded. It is his duty, in case of obvious and certain disability, or dangerous ignorance or mistake on the part of the pilot, to dispossess him of his authority. So it is the duty of the master to see that a lookout is kept; and generally, while the orders of the pilot are imperative as to the course the vessel is to pursue, the management of it is still under the control of the master. The pilot is the servant of the owner of the vessel, and the latter is generally liable to third persons for any damage resulting from his negligence or fault. But if, as when a vessel is entering a port, the master is obliged to take the first pilot that offers, or pay a certain amount, it would seem that such taking is by compulsion, and that the owner should not be liable for his acts. This is the settled law in England, but it is perhaps still an open question in the United States.