The Picture Exchange Communication System (PECS) is a widely used intervention strategy designed to teach communication skills to children with developmental delays, including autism. The Picture Exchange Communication System incorporates the teaching of mand initiations that are thought to be pivotal response behaviours, and have been demonstrated to lead to generalised improvements in other nontargeted behaviours. The aim of the present study was to assess the acquisition of PECS with a 3-year-old boy with autism using the established PECS training program, and to evaluate concomitant changes in spoken language, social–communicative behaviours, and functional play. Results indicated that the participant rapidly acquired the criterion behaviours for Phases 1 to 3 of the PECS program. Although PECS exchanges were rarely observed in the generalisation settings, clear increases were evident in verbal mands and other initiations in both home and kindergarten generalisation settings. Increases in spoken vocabulary and in the length of comprehensible spoken utterances in free-play were observed as were gains in time spent in developmentally appropriate play. Implications of these results and directions for future research are discussed.