Youth with disabilities are overall less engaged in extracurricular, community, and social activities than their peers without disabilities. Specifically, youth with intellectual and developmental disabilities (IDD; e.g., autism, intellectual disability) are less likely to participate in extracurricular or social activities compared to peers with other disabilities (e.g., learning disability; Lipscomb et al., 2017). Religious congregations may be one of the most prominent resources in rural communities (Institute for Emerging Issues, 2018) and underrepresented communities (Pargament, 1998) and can hold be an important resource for youth with IDD and their family members (Carter, 2021; Liu et al., 2014). However, leaders of religious congregations (e.g., clergy; religious education directors) may not know how to support and include youth with IDD in their congregation. This mixed-method study measured the effects of an asynchronous professional development to train religious leaders in strategies for supporting youth with IDD in their religious congregations. Participants in the treatment group who participated in the professional development training demonstrated significantly higher scores in knowledge and confidence implementing Inclusive Language and Inclusive Learning than participants in the control group. Participants also identified opportunities, barriers, and implementation drivers to implementing Inclusive Language and Inclusive Learning in religious congregations. [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.]