Abstract
The use of physical shaping and imitation as a means of teaching signs were compared. Three profoundly intellectually disabled individuals were taught two basic signs. These subjects had failed to learn signs under an imitation condition in a previous investigation. The subjects' performance during training was compared under the two treatment conditions using an alternating treatments design. The results indicated that imitation was not a useful technique with these individuals, but that physical shaping led to significant improvements in all subjects' learning of the signs. The implications of the findings for clinical practice and the practicability of empirical case designs for future research are discussed.