EPOSIM is a community-based participatory research study which used the Photovoice method with people who inject drugs (PWID) ahead of a possible opening of a drug consumption room (DCR) in Marseille, France. It aimed to identify the strategies used by PWID when injecting, and the risks they take when they have no safe private space to inject in the area they live in. A total of 7 PWID participated in the full study process. The 189 photographs they took provided us with a good understanding of their injection practices in public places. The main results highlighted the spatiality and materiality of injecting experience in a context where no DCR was available. They also showed the relevance of Photovoice to valorize the voices of PWID when implementing a DCR. Through the showcasing of their photographs at various public exhibitions, the participants seized the opportunity to use Photovoice to make their voices heard beyond the group formed for the study, in order to show the different forms of stigma and insalubrious contexts which they faced on a daily basis. Furthermore, the photographs taken demonstrated that having only health and safety records is not enough to fully understand PWID injection practices. Future studies must take into account PWID perceptions of their relationship with injecting in public spaces and with the management of stigma. The questions of pleasure and comfort must also be explored in evaluation studies of harm reduction measures, for example, DCR.