The purpose of this paper was to study the effect of therapeutic positioning on the functional use of augmentative communication equipment. Recent literature on therapeutic positioning as it affects muscle tone and functional activities is reviewed. The effect of positioning intervention on rate and accuracy of head-controlled typing on an augmentative communication machine was measured. The rate of typing was found to increase significantly and the percentage of accuracy was found to decrease significantly with positioning intervention. A third measure combining rate and accuracy (accuracy rate) also increased enough to reach statistical significance. These results suggest that positioning changes do affect head control in the functional use of a communication machine. Because of the combined areas of expertise needed to adequately address positioning, head control, communication, and overall function, a team approach to clients with these concerns is advocated.