Teachers in early childhood classrooms face a diverse child population, including children with developmental delays and differences (DD), requiring teachers to exhibit professional skills to address a broad spectrum of developmental needs. At times, early learners with and without DD exhibit challenging behaviors (e.g., aggression, tantrums). Nevertheless, teachers find themselves ill-prepared to manage such behavior and teach under these circumstances due to limited training in classroom behavior management. Applied Behavior Analysis (ABA) is an effective treatment for children with various developmental differences and has proven successful in classroom settings when applied. This report describes a behavior consultation model used in a four-year project in 44 early childhood classrooms with 196 teachers and 97 children identified as having developmental delays and challenging behavior. Recommendations for choosing a behavior consultant for similar settings and a discussion of recurring behavior strategies recommended are presented. (author abstract)