Mands, of which requesting and rejecting responses are considered subclasses, are the first emerging communication functions that allow children to express their wants and needs. While typically developing children develop speech without specifically designed intervention, many children with autism and developmental disabilities are likely to rely on prelinguistic communication forms that are socially and developmentally inappropriate or unacceptable until symbolic forms of functional communication are taught. A review of the literature on teaching mands indicates that although there is an abundance of research addressing teaching communicative requesting behaviors, rarely have studies attempted to teach communicative rejecting. The purpose of this study was to create rejecting opportunities using the wrong-item format embedded into the missing item format, and to teach socially appropriate rejecting response using AAC for four children with autism and developmental disabilities. This study employed a multiple probe design across four participants to examine the effectiveness of the procedure. Results indicated that the wrong-item format embedded into the missing-item format was effective in teaching symbolic forms of rejecting responses using VOCAs and PECS. The results were generalized across two untrained activities and were maintained up to four weeks following the termination of generalization probes for three participants. The implications and limitations of this study, as well as potential topics for future research are also discussed. / text