Parent management training is an evidence-based treatment for disruptive behavior. However, the number of treatment sessions can be high, contributing to high attrition rates. The purpose of this study was to examine post-treatment, 6-month, and 1-year treatment outcomes of the Brief Behavioral Intervention. One hundred twenty children aged 2-6.5 years demonstrating clinically significant disruptive behavior were referred to an outpatient clinic for treatment and participated in the study. Attrition was below reported rates in the literature. Significant decreases in child disruptive behavior and parent stress were found from pre-to-post intervention, and improvements were maintained at follow-ups. Significant pre-to-post intervention teacher reported decreases in behavior were reported.