Abstract: In a fixture for supporting a workpiece in a machine tool by means of two support elements held in a housing with the workpiece lying on them, the support elements are configured as levers held in a rotating mounting in the housing, the levers being driveably connected together by means of a threaded spindle. The threaded spindle has counter-rotating thread sections in areas corresponding to the support elements, and each of the counter-rotating thread sections of the spindle engage in a sliding block, the sliding blocks being rotatably mounted in holes in the support elements. The threaded spindle is provided with a device for locking the support elements in a set operating position. The two support elements are jointly adjustable and lockable, so that they can be set and readjusted within a short time and in a manner so that production inaccuracies are precluded.