Abstract: This invention relates to a telecommunication control switching device (1) and method for controlling the power supply to an electrical device (8) through a telecommunication network (3). A device (1) of the present invention is connected between the telecommunication line (3) and a piece of telecommunication equipment, such as a telephone, as well as being connected between a mains supply (6) and an electrical appliance (8). The device (1) provides a switched mains outlet, and monitor given conditions in the telecommunications lines (3)/telecommunication equipment. The device (1), therefore, enables the electrical appliance (8) to automatically be switched on or off when those given conditions such as a ringing signal or off-hook situation in a telephone set, occur.