Abstract: As a chronic relapsingc ondition, drug use is a major risk factor for HIV infection and lower access to HIV medications. Identifying factors associated with sustained cessation can contribute meaningfully to HIV prevention and treatment. The purpose of this case-control study is to characterize the individual and neighborhood-level determinants of initial and sustained cessation of heroin use among persons who report a history of chronic heroin use within economically disadvantaged, predominantly racial/ethnic minority neighborhoods in New York City. Data are sparse on the prognostic indicators and course of sustained heroin cessation, particularly in street-recruited samples. Likewise, while cessation makes sense in terms of parenteral HIV prevention, heroin dulls libido, and little is known about levels of sexual risk following heroin cessation short or long term. This study seeks to isolate potentially modifiable factors to assist the overall goal of sustained abstinence if not risk reduction. Key to this study is our recognition of cessation as not only an outcome, but also a possible exposure associated with sexual risk behavior.