Cumulative traumatic migration experiences are compounded by escalating chronic distress related to the current sociopolitical climate for refugee and immigrant children and families. The aim of this open trial was to conduct a preliminary evaluation of You're Not Alone, a rapidly mounted, strengths-based, community-focused capacity building training initiative for stakeholders interacting with refugee and immigrant children and families in the Chicago area. Trainings, based on Trauma-Informed Care (TIC) and psychological first aid frameworks, adapted education and universal health promotion strategies for population-specific chronic traumatic stress. Two groups of participants (N = 948), who attended either mandatory (n = 659 educators) or voluntary (n = 289 community stakeholders) trainings, completed surveys at pretraining, post-training, and 6-week follow-up. Outcome indices included participant satisfaction, acceptability of training model, and changes in knowledge, attitudes, and behaviors. Over 90% of participants reported satisfaction and acceptability of trainings. For educators, hierarchical linear modeling analyses demonstrated significant increases in trauma knowledge, refugee and immigrant-specific knowledge, positive attitudes toward TIC over time, and a decrease in negative attitudes toward immigrants. Over 95% of participants indicated that they learned and intended to use new strategies to help serve refugee and immigrant children and families. At follow-up, over 80% of those who completed the survey had utilized at least one strategy, and over 55% indicated that they were using resources that they learned about in the training. This study demonstrates that capacity-building trainings swiftly developed and disseminated to community stakeholders can produce positive change in knowledge, attitudes, and practices. (PsycInfo Database Record (c) 2023 APA, all rights reserved).