“…Peers also play an important role in homeless adolescents' use of substances. Other homeless youths become the source of information and support but do not encourage prosocial behavior, are similarly troubled, and use drugs/alcohol (Thompson, Pollio, Constantine, Reid, & Nebbitt, 2002;Whitbeck & Hoyt, 1999). Research indicates that street friends provide an important learning environment for initiating drug use and provide opportunities and reinforcement for drug-using behavior (Kipke, Montgomery, Simon, & Iverson, 1997).…”