A biofeedback training system has been developed for providing the cerebral palsied child with precise auditory and visual information regarding the spatial position of his head. The child actively practices correcting his head position by using feedback delivered through a mercury-switch device called a head position trainer. Twelve children have received clinical training and results are discussed in terms of feedback-sensitive, feedback-trained and feedback-learned, the results of treatment dictating the classification. It is concluded that the head position trainer is an effective sensory aid for the cerebral palsied child in the development of head control and position awareness. It is proposed that this system has excellent potential use as an adjunct to regular therapy programming in that it provides additional daily practice time and an objective method of recording the child's progress.