Prevent, Teach, and Reinforce for Families (PTR-F) has been found effective in increasing parents' use of positive behavior support (PBS)-based strategies and decreasing children's challenging behavior. However, only few studies have purposefully explored the effectiveness of PTR-F for culturally and linguistically diverse (CLD) families. To address this gap, the current study explored modifications that can enhance PTR-F's cultural responsivity and examined its effectiveness on CLD families. This mixed methods study used a single-case research design to examine the effectiveness of PTR-F on parents' use of Behavior Support Plan (BSP) strategies and the effectiveness of parents' use of BSP strategies on child challenging behaviors. Qualitative interviews were conducted to understand the perspectives of CLD parents on the contextual fit of PTR-F and BSP. The results suggest that the modified PTR-F process was functionally related to parents' use of BSP strategies and that parents' use of BSP strategies was also functionally related to reductions in child challenging behavior. CLD parents who participated in this study found the PTR-F process and their BSPs contextually fit and socially valid. This study contributes to expanding the current literature on the effectiveness of PTR-F by focusing on the voices of CLD families and investigating how their contextual factors affect the effectiveness of PTR-F. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]