Information about the characteristics of street-living versus shelter-residing youth is vital for tailoring prevention and intervention efforts to the unique needs of runaway and homeless youth. The present study compared two samples of youth [street-living (n=73) versus shelter-residing (n=205)], between the ages of 14 to 17 years, on behavioral and emotional factors and service use. Based on the different characteristics of the two groups, the predictors explaining the living status of the runaways and homeless youth were explored. In general, street-living youth reported more severe substance use, depressive symptoms, and risky sexual behavior, but less lifetime service involvement compared to shelter-residing youth. The factors that predicted shelter-residing status were related to younger age, prior service care experience, more knowledge about HIV, and engaging in less delinquent and risky behavior. Given the little overlap among youth in service involvement and the greater severity faced by street-living youth, the conclusions highlight the need for increased funding and attention towards facilitating the ability of street-living youth to find and enter mental health and reintegration services.