A lighting apparatus (2) includes a housing (4) of plastic material, the housing (4) defining a translucent window (12), and a light emitting diode assembly (3) on a printed circuit board (34). The apparatus (2) may be attached to the hull (14) of a boat by means of a flange (10) and a nut (16). The apparatus (2) may include a heat sink (36) machined from a solid aluminium bar. The housing (4) may be connected to a sealing cap (6). The housing (4) is preferably injection-moulded from a thermoplastic material such as polycarbonate. Electrical wires may extend through a central bore (42) of the heat sink (36) and the sealing cap (6).