Abstract
Several candidate vaccines for hepatitis C are currently in preclinical development or the early stages of clinical trials. Implementing trials of these vaccines among people who inject drugs will be challenging. Previous research, particularly willingness to participate studies in relation to HIV vaccines in marginalised groups, has focused on the modifiable characteristics of individual participants. This qualitative research with people who inject drugs, health staff and clinicians focuses on social, organisational and structural elements of vaccine trial designs which may exclude or reduce the participation of people who inject drugs.