The Biobehavioral Epidemiology and Substance Abuse program section is led by Drs. Pamina Gorbach (Director) and Steven Shoptaw (co-Director). The section focuses on how substance use influences HIV disease and its goal is to foster translational science amongst basic scientists, behavioral scientists, and substance use researchers. Drs. Gorbach and Shoptaw are also co PIs of the NIDA-funded mSTUDY, a UCLA-based cohort of substance using minority (Black or Latino) men who have sex with men (MMSM). Of these, about one-half are HIV-positive; the other half are HIV-negative MMSM at high-risk for HIV acquisition. When at full size, this cohort will comprise 620 MMSM with repeated data visits spaced every six months from an enrolled cohort of approximately 1,080 MMSM. It not only provides a well-characterized, extensive repository of samples for leveraged use with other cohorts and sub studies to address the questions of this project, but is also a critical platform for research to facilitate collaboration with other investigators. mSTUDY’s clinical, behavioral and biospecimen data are available to outside researchers and are thus a centerpiece of the program section. The program section is committed to the integration of behavioral epidemiology and expertise in measures; biological outcomes/specimens; clinical expertise; and substance use expertise. Dr. Shoptaw is also the co-Director of the affiliated UCLA Center for HIV, Identification, Prevention, & Treatment Services (CHIPTS).