Language and communication skills are important predictors of long-term outcome for children with autism spectrum disorders (ASD) (Stone & Yoder, 2001) and therefore they are a priority for families and service professionals. A notable core deficit amongst children with ASD is the variable rate of development and range of functional outcomes in language compared to typically developing peers (Wetherby, 2006). Although approximately a quarter of children with ASD are nonverbal (Wendt, 2009), intervention literature targeting language is limited in regard to children who have little or no verbal language by the time they exit the preschool years (Lord et al., 2005). Preverbal communication skills, specifically joint attention abilities have been identified as predictors of language development (Mundy & Crowson, 1997). Prior to verbal language development, parents are instrumental at initiating and responding to bids for joint attention with their children (Schertz & Odom, 2007). A transactional model of development (Sameroff, 2010) emphasizes the significance of bidirectional exchanges between child and environment as the context for early learning. Congruent with this theory, a parent's ability to engage and then maintain his or her child in periods of joint engagement has been reported to predict a child's language growth (Siller & Sigman, 2002). This randomized control trial will examine parents' ability to learn and implement a novel joint engagement intervention (Kasari, Freeman & Paparella, 2006) designed to target the core symptom domain of language and communication with their child who is nonverbal despite intensive intervention programming up to age five.