Although most youth who become homeless return to their parents or guardians, some experience multiple or lengthy episodes of homelessness. This research brief highlights interventions that address characteristics and experiences associated with prolonged homelessness: unstable housing and living situations, higher school dropout and unemployment rates, substance use and mental health challenges, and involvement in the child welfare system. It identifies promising interventions intended for similar at-risk populations. These interventions include supportive housing, programs that support education and employment, programs to reduce substance abuse and support youth with mental health challenges, and programs for youth in the child welfare system. No tested interventions specifically addressing prolonged youth homelessness were identified, indicating large gaps in the research.