Advances in augmentative and alternative communication research for individuals with Autism spectrum disorder: moving research and practice forward.

Augmentative and alternative communication (AAC) approaches offer expressive and receptive supports for the segment of the population of individuals with autism spectrum disorder (ASD) who have little or no functional speech. The National Center for Autism Evidence and Practice (NCAEP) declared augmentative and alternative communication (AAC) interventions for individuals with autism an "evidence-based practice." Following a brief analysis of the breakdown of studies included in NCAEP by dependent variable, we introduce each of the four papers published as part of this special issue on Advances in Augmentative and Alternative Communication Research for Individuals with Autism Spectrum Disorder. In addition to elucidating the contributions and advances of each paper to the research base, including the NCAEP report, we provide a critical commentary as applicable in the hopes of stimulating and guiding further research.