This Workshop introduces participants to an evidence-based treatment modality for use with disruptive preschoolers: Parent Child Interaction Therapy (PCIT). PCIT research has demonstrated statistically and clinically significant improvements in disruptive behaviors and ADHD symptoms of preschool children, with promising maintenance of treatment effects. Child and adolescent psychiatrists should be familiar with PCIT as an important evidence-based treatment option. The Workshop describes the theoretical and empirical basis of this treatment approach; reviews the assessment procedures that guide the course of treatment, determine treatment termination, and evaluate treatment outcome; reviews the basic PCIT skills parents learn, the process for teaching those skills, and the skills therapists must use to coach parents; and illustrates the course of change in disruptive behavior during treatment.