Phillip Marotta is a doctoral student concentrating in Social Welfare Practice at Columbia University School of Social Work. His present research interests include empirical inquiry into the impact of incarceration on HIV drug and sexual risk factors, rates of infectious diseases, retention in care and engagement in behavioral HIV prevention interventions. Phillip's program of research centers on the role of multi-level influences in shaping the social production of HIV risk behaviors. His past research projects have included cross-national analyses of the effects of harm reduction program implementation and economic drivers on rates of HIV infection overall and among people who inject drugs in 28 countries in Europe. He is currently researching the impact of involvement in the criminal justice system on HIV risk among population who use drugs in the United States, Kazakhstan, Tajikistan and Afghanistan. Prior to coming to Columbia his work included adolescent sexual health as a junior research scientist at New York University Center for Latino and Adolescent Health, research associate on a family planning research study at Department of Population and Family Health at Columbia University Mailman School of Public Health. Phillip received his MPH from Columbia Mailman School of Public Health, his MSSW from Columbia University School of Social Work, and his B.A in History from Wagner College. Immediately following his masters degree, Phillip Marotta successfully completed a one year Post-Masters clinical training fellowship in Psychiatry at Yale University School of Medicine in the Department of Psychiatry.