The long-term goals of this study are to foster development and dissemination of evidence-based behavioral and pharmacological treatments to reduce HIV transmission, injection drug use (IDU), and heroin use in Russia. This study will examine the effects of combining behavioral therapy with naltrexone pharmacotherapy for the treatment of opiate dependence and reduction of HIV risks in opiate dependent individuals. Specifically the study will determine whether extended-release injection naltrexone has greater efficacy and is more cost-effective than oral naltrexone maintenance, whether behavioral drug and HIV risk reduction counseling (BDRC) combined with brief, medical management (MM) has greater efficacy and is more cost-effective than MM only, and whether particular combinations of medication formulation and counseling (MM only or MM plus BDRC) have greater efficacy or are more cost-effective than other combinations.