This study conducted an in-depth analysis of the efficacy of the Decision Model in the development of function-based treatments for disruptive behaviors in four toddlers with disabilities aged from 26 to 34 months in inclusive toddler classrooms. The research was conducted in three parts. In Part 1, a functional behavioral assessment was conducted to identify the function(s) of the disruptive behavior. In Part 2, behavioral treatments, developed and designed using the Decision Model, were systematically constructed for each toddler. In Part 3, the treatment was implemented in the inclusive toddler program during the most problematic naturally occurring activities for each child. The function-based treatments resulted in a significant increase in the child's replacement behaviors. Additionally, special education teachers' social validity ratings indicated that the individualized function-based treatments were preferable to the previous behavior management strategies.