The Corporation of Trinity House of Deptford Strond, also known as Trinity House (and formally as The Master, Wardens and Assistants of the Guild Fraternity or Brotherhood of the most glorious and undivided Trinity and of St Clement in the Parish of Deptford Strond in the County of Kent), is the official authority for lighthouses in England, Wales, the Channel Islands and Gibraltar. Trinity House is also responsible for the provision and maintenance of other navigational aids, such as lightvessels, buoys, and maritime radio/satellite communication systems. It is also an official deep sea pilotage authority, providing expert navigators for ships trading in Northern European waters.