Recent political events and policy changes in the United States have fueled antirefugee/immigrant rhetoric and an increase of xenophobic harassment and intimidation, which together present a significant threat to the physical and mental health of refugee/immigrant children and families. This article aims to provide an overview of how the current sociopolitical context threatens the public health of refugee and immigrant communities and to describe the role of psychologists in advocating for social justice and responding to this urgent public health need through interprofessional collaboration and translation of scientific knowledge into multilevel intervention development. The case study of the You're Not Alone (YNA) initiative describes swiftly mobilized advocacy efforts (e.g., press conference, webinars, resources development and dissemination) and participatory development and roll-out of community capacity-building trainings to address the needs of refugee/immigrant children and families. Trainings aimed to raise awareness of the refugee/immigrant experience and to equip refugee/immigrant community members and providers across a variety of public sectors to implement culturally responsive and trauma-informed strategies to promote resilience, respond to distress, and prevent mental health crises. Between March 2017 and June 2018, a total of 1,642 individuals attended 48 training events. The role of psychologists in future policy and advocacy efforts to promote mental health among refugee/immigrant families is discussed as well as implications for how other marginalized communities affected by the current sociopolitical climate might benefit from broadening the scope of this public health response. (PsycINFO Database Record (c) 2019 APA, all rights reserved).