A light socket having a standard contact and switch arrangement for standard operation with three-way incandescent light bulbs. In addition to the standard main switch, the socket also includes a secondary mode switch operatively connected to the appropriate terminals such that placing the mode switch in a first position will provide proper operational sequence with a three-way light bulb, while placing the mode switch in a second position will provide the proper operational sequence for a one-way light bulb. This mode switch may also be provided in an adapter which is formed to be received within the receptacle of a standard three-way light socket, and which also includes a standard receptacle for the receipt of the light bulb.