The present study examines risk factors for running away and homelessness among a sample of more than 7,000 currently housed youth using the National Longitudinal Study of Adolescent Health (Add Health). Structural equation modeling results revealed that those with greater levels of family instability and those who ran away at Wave 2 were significantly more likely to run away and/or become homeless 5 years later at Wave 3. Family instability also had a significant indirect effect on running away and/or being homeless at Wave 3 through greater levels of problem behaviors and running away at Wave 2. Running away at Wave 1 was indirectly associated with running away and/or becoming homeless at Wave 3 through family instability, problem behavior, and Wave 2 running. (Contains 1 figure, 2 tables and 2 notes.)