By definition children with autism spectrum disorders (ASD) experience difficulty understanding and using language. Accordingly, visual and picture-based strategies such as the Picture Exchange Communication System (PECS) show promise in ameliorating speech and language deficits. This study reports the results of a multiple baseline across participants investigating the implementation of the PECS with three preschool children with characteristics of ASD. The first four phases of PECS were taught to the participants: basic picture exchange, increasing distance use of PECS, discriminating among a variety of pictures, and communicating in sentences composed of pictures. Relative to the impact of PECS's implementation in providing the participants with a functional communication system, word approximations, and intelligible word and phrase use, results indicated that two of the three participants mastered PECS. However, participants did not significantly increase in use of word approximations and intelligible words.