Homelessness results from an interaction of structural determinants and individual vulnerabilities, creating various pathways into homelessness and having multilevel impacts. Understanding and addressing homelessness requires research that not only takes an ecological perspective but also can be translated into action. Despite research demonstrating differing needs and experience among various subpopulations, particularly marginalized groups, homeless service systems often take a one-size-fits-all approach. Additionally, homeless service systems’ prioritization of the most vulnerable and chronically homeless for permanent housing programs results in a service system that operates in a state of triage, with minimal attention to prevention efforts. This special issue highlights actionable research focused on preventing homelessness and addressing disparities among marginalized groups. Included articles target homelessness at multiple levels using a combination of qualitative, quantitative, and mixed-methods approaches. Embedded in community psychology values, these studies focus on prevention, leverages participatory methods, relies on diverse lived experiences, and explores community-based solutions.