Selecting an appropriate mode of communication is an important clinical decision when beginning an augmentative and alternative communication (AAC) intervention. In the present study, we investigated whether two boys with significant intellectual disabilities would show a preference for using one of three AAC devices. Initially, the boys were taught to use three AAC devices (i.e., Cyrano Communicator, Mini-MessageMate, and a Picture Communication Board) using a multiple-probe-across-devices design. One participant was successful with only one device, while the other was successful in acquiring basic use of all three devices (i.e., making a request using the device and demonstrating correspondence between the picture icon and item requested). The child who acquired basic use of all three devices participated in the second phase. A choice assessment was conducted using a free-operant paradigm to determine which of the three devices he preferred. In the final phase, the most preferred device was targeted for more specific instruction (i.e., retrieving the device from a distance, turning the device on, approaching a communication partner, getting the communication partner's attention, and using the device to make a request), using a changing criterion design. Results for this participant indicated that he had a clear preference for one device and was able to learn how to use it in a more functional manner. Limitations and suggestions for future research are discussed.