The Positive Health (pH) project is a cohort study of HIV positive people. The aim of the study is to monitor responses to HIV and treatments over time, particularly in relation to engagement with health care services, health beliefs, preventive behaviour and medication use. The main focus of the study is on positive people’s health management strategies and the impact of HIV on their lives. Participants were recruited through two research centres: one in NSW and one in Victoria. The criterion for entry into the study was being HIV positive. The project is administered collaboratively through the National Centre in HIV Social Research (NCHSR), the National Centre in HIV Epidemiology and Clinical Research (NCHECR), the Australian Research Centre in Sex, Health and Society (ARCSHS), the National Association of People Living with HIV/AIDS (NAPWA) and the Australian Federation of AIDS Organisations (AFAO). A description of the sample of 425 participants is contained in this report. Detailed analyses of the data will be published as they are completed. The descriptions of the data presented here are not final and further analyses may require some reinterpretation of the findings.