RecruitingPhase 2Behavioural interventionOptimizing Outcomes for Young Autistic ChildrenThe overarching goal of the proposed study is to: (a) determine how best to sequence two parent-mediated interventions: a social communication intervention (Project ImPACT, Improving Parents as Communication Teachers) and a disruptive behavior intervention (Parent Training for Disruptive Behavior) and (b) examine moderators and mediators of intervention outcomes.