Comprehensive evidence-based interventions are needed to help early childhood educators manage challenging student behaviors. One such intervention, class-wide function-related intervention teams (CW-FIT), is a multi-tiered behavioral intervention program based on positive behavior support principles, including four main elements: (a) teaching socially appropriate communication skills, (b) using differential reinforcement with an interdependent group contingency, (c) extinguishing or eliminating potential reinforcement for problem behavior, and (d) implementing individual interventions using self-management, help cards, and/or functional assessment. This study implemented CW-FIT with five kindergarten through second grade teachers. Results demonstrated efficacy of the program as early childhood teachers increased their praise rates and decreased their reprimand rates, and students responded with increased on-task behavior and fewer classroom disruptions. Study implications and limitations are addressed. [This paper was published in "Early Childhood Education Journal" v43 n5 p357-365 2015 (EJ1071428).]