Autism spectrum disorder (ASD) begins in early childhood and is characterized by impairments in social interaction and communication, restricted interests and repetitive behavior. As many as half of children with ASD between the ages of 3 and 8 also exhibit disruptive behaviors that interfere with their overall development and family functioning. This Therapist Guide, Parent Training for Disruptive Behavior, is designed for therapists to use with parents of children with ASD and challenging behaviors, such as tantrums, noncompliance, and aggression. Based on the principles of Applied Behavior Analysis and developed over more than a decade of research, the intervention consists of 11 core sessions as well as supplemental sessions, a home visit, and follow-up visits. Each session includes a therapist script, activity sheets, parent handouts, and checklists. Video vignettes are available online to illustrate concepts. The treatment manual is designed to be used in conjunction with the companion Workbook for parents. Each session is delivered individually in weekly outpatient visits. Homework assignments between sessions focus on implementing behavior change strategies collaboratively chosen by the therapist and parent.