Abstract: In a preferred embodiment, a device for indicating rotation of the head of a golfer during the process of hitting a golfball, which includes: a housing; a sensor including a pendulum switch disposed in the housing to sense the beginning of rotation of the head from an initial position, generally about the axis of the spine of the golfer, and to produce an output signal thereupon; a sound producing device activatable in response to the output signal to provide an audible signal to the golfer; an adjustment device to adjust the sensor so that the sensor will not produce the output signal when the head is in a desired position, but will produce the output signal when the head begins to rotate in the direction the golfball will be hit; and a manually initiated timing device to which the sensor is responsive to permit the sensor to produce the output signal only during a selected period of time after manual initiation of the timing device.