|Pivotal Response Treatment (PRT) is a comprehensive naturalistic intervention model based on the principles of Applied Behavior Analysis (ABA) that aims to teach pivotal behaviors to children with autism spectrum disorder (ASD) in order to achieve generalized improvements in their functioning. Several studies have shown that PRT results in improvements in communication, language, play skills, and affect and reductions in problem behaviors in young children with ASD (Verschuur, Didden, Lang, Sigafoos, & Huskens, 2014), but additional research is necessary. During this PhD project, we will conduct a series of studies to broaden the application of PRT and to contribute to the evidence base of PRT. First, we will investigate the effectiveness of staff training in PRT on staff member-created opportunities and self-initiations and language, pragmatic, and adaptive skills of school-aged children with ASD. Generalization and maintenance will also be examined. Because there is great deal of variability in implementation of PRT across staff (Verschuur et al., 2014), we will also investigate the association between fidelity of PRT implementation and staff characteristics (e.g., personality, child-staff member relationship, attitude towards evidence-based interventions, work stress). Third, we will investigate the differential effectiveness of group and individual parent training in PRT on parent behaviors (parent-created opportunities, parental stress, and self-efficacy) and child behaviors (self-initiations and maladaptive behaviors). Finally, because only a few studies investigated the implementation of PRT in a school setting, we will also investigate to effectiveness of teacher training in classroom PRT on teachers’ fidelity of implementation and children's communication skills and maladaptive behaviors. Maintenance of these skills will also be examined.